diff --git a/app/components/ComponentItem.vue b/app/components/ComponentItem.vue
index 8624d41..905feab 100644
--- a/app/components/ComponentItem.vue
+++ b/app/components/ComponentItem.vue
@@ -461,16 +461,39 @@ const extractStructureCustomFields = (structure) => {
 }
 
 function fieldKeyFromNameAndType(name, type) {
-  const normalizedName = typeof name === 'string' ? name.trim() : ''
-  const normalizedType = typeof type === 'string' ? type : ''
+  const normalizedName =
+    typeof name === 'string' ? name.trim().toLowerCase() : ''
+  const normalizedType =
+    typeof type === 'string' ? type.trim().toLowerCase() : ''
   return normalizedName ? `${normalizedName}::${normalizedType}` : null
 }
 
+function resolveOrderIndex(field) {
+  if (!field || typeof field !== 'object') {
+    return 0
+  }
+  if (typeof field.orderIndex === 'number') {
+    return field.orderIndex
+  }
+  if (
+    field.customField &&
+    typeof field.customField.orderIndex === 'number'
+  ) {
+    return field.customField.orderIndex
+  }
+  return 0
+}
+
 function deduplicateFieldDefinitions(definitions) {
   const result = []
   const seen = new Set()
 
-  ;(Array.isArray(definitions) ? definitions : []).forEach((field) => {
+  const orderedDefinitions = (Array.isArray(definitions)
+    ? definitions.slice()
+    : []
+  ).sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b))
+
+  orderedDefinitions.forEach((field) => {
     if (!field || typeof field !== 'object') {
       return
     }
@@ -490,6 +513,7 @@ function deduplicateFieldDefinitions(definitions) {
     if (key) {
       seen.add(key)
     }
+    field.orderIndex = resolveOrderIndex(field)
     result.push(field)
   })
 
@@ -530,10 +554,16 @@ function mergeFieldDefinitionsWithValues(definitions, values) {
     if (!matchedValue) {
       return {
         ...field,
-        value: field?.value ?? ''
+        value: field?.value ?? '',
+        orderIndex: resolveOrderIndex(field),
       }
     }
 
+    const resolvedOrder = Math.min(
+      resolveOrderIndex(field),
+      resolveOrderIndex(matchedValue.customField),
+    )
+
     return {
       ...field,
       customFieldValueId: matchedValue.id ?? field.customFieldValueId ?? null,
@@ -543,7 +573,8 @@ function mergeFieldDefinitionsWithValues(definitions, values) {
         fieldId ??
         null,
       customField: matchedValue.customField ?? field.customField ?? null,
-      value: matchedValue.value ?? field.value ?? ''
+      value: matchedValue.value ?? field.value ?? '',
+      orderIndex: resolvedOrder,
     }
   })
 
@@ -583,23 +614,30 @@ function mergeFieldDefinitionsWithValues(definitions, values) {
         required: entry.customField?.required ?? false,
         options: entry.customField?.options ?? [],
         value: entry.value ?? '',
-        customField: entry.customField ?? null
+        customField: entry.customField ?? null,
+        orderIndex: resolveOrderIndex(entry.customField),
       })
     }
   })
 
-  return merged
+  return merged.sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b))
 }
 
 function dedupeMergedFields(fields) {
   if (!Array.isArray(fields) || fields.length <= 1) {
-    return Array.isArray(fields) ? fields : []
+    return Array.isArray(fields)
+      ? fields.slice().sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b))
+      : []
   }
 
   const seen = new Map()
   const result = []
 
-  fields.forEach((field) => {
+  const orderedFields = fields
+    .slice()
+    .sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b))
+
+  orderedFields.forEach((field) => {
     if (!field || typeof field !== 'object') {
       return
     }
@@ -617,12 +655,14 @@ function dedupeMergedFields(fields) {
     const key = fieldId || nameKey
 
     if (!key) {
+      field.orderIndex = resolveOrderIndex(field)
       result.push(field)
       return
     }
 
     const existing = seen.get(key)
     if (!existing) {
+      field.orderIndex = resolveOrderIndex(field)
       seen.set(key, field)
       result.push(field)
       return
@@ -640,11 +680,15 @@ function dedupeMergedFields(fields) {
 
     if (!existingHasValue && incomingHasValue) {
       Object.assign(existing, field)
+      existing.orderIndex = Math.min(
+        resolveOrderIndex(existing),
+        resolveOrderIndex(field),
+      )
       seen.set(key, existing)
     }
   })
 
-  return result
+  return result.sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b))
 }
 
 const componentDefinitionSources = computed(() => {
diff --git a/app/components/CustomFieldsDisplay.vue b/app/components/CustomFieldsDisplay.vue
index c75fb76..8f35667 100644
--- a/app/components/CustomFieldsDisplay.vue
+++ b/app/components/CustomFieldsDisplay.vue
@@ -5,7 +5,7 @@
     </h4>
     <div class="grid grid-cols-1 md:grid-cols-2 gap-4">
       <div
-        v-for="field in customFields"
+        v-for="field in sortedCustomFields"
         :key="field.id"
         class="form-control"
       >
@@ -81,7 +81,7 @@
 </template>
 
 <script setup>
-import { ref, reactive, onMounted, watch } from 'vue'
+import { ref, reactive, onMounted, watch, computed } from 'vue'
 
 const props = defineProps({
   customFields: {
@@ -101,6 +101,17 @@ const props = defineProps({
 
 const emit = defineEmits(['update'])
 
+const sortedCustomFields = computed(() => {
+  if (!Array.isArray(props.customFields)) {
+    return []
+  }
+  return [...props.customFields].sort((a, b) => {
+    const left = typeof a?.orderIndex === 'number' ? a.orderIndex : 0
+    const right = typeof b?.orderIndex === 'number' ? b.orderIndex : 0
+    return left - right
+  })
+})
+
 // Valeurs des champs personnalisés
 const fieldValues = reactive({})
 
diff --git a/app/components/PieceItem.vue b/app/components/PieceItem.vue
index 85d439b..78ef383 100644
--- a/app/components/PieceItem.vue
+++ b/app/components/PieceItem.vue
@@ -456,16 +456,36 @@ const extractStructureCustomFields = (structure) => {
   return Array.isArray(customFields) ? customFields : [];
 };
 function fieldKeyFromNameAndType(name, type) {
-  const normalizedName = typeof name === 'string' ? name : '';
-  const normalizedType = typeof type === 'string' ? type : '';
+  const normalizedName =
+    typeof name === 'string' ? name.trim().toLowerCase() : '';
+  const normalizedType =
+    typeof type === 'string' ? type.trim().toLowerCase() : '';
   return normalizedName ? `${normalizedName}::${normalizedType}` : null;
 }
 
+function resolveOrderIndex(field) {
+  if (!field || typeof field !== 'object') {
+    return 0;
+  }
+  if (typeof field.orderIndex === 'number') {
+    return field.orderIndex;
+  }
+  if (field.customField && typeof field.customField.orderIndex === 'number') {
+    return field.customField.orderIndex;
+  }
+  return 0;
+}
+
 function deduplicateFieldDefinitions(definitions) {
   const result = [];
   const seen = new Set();
 
-  (Array.isArray(definitions) ? definitions : []).forEach((field) => {
+  const orderedDefinitions = (Array.isArray(definitions)
+    ? definitions.slice()
+    : []
+  ).sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b));
+
+  orderedDefinitions.forEach((field) => {
     if (!field || typeof field !== 'object') {
       return;
     }
@@ -482,6 +502,7 @@ function deduplicateFieldDefinitions(definitions) {
     if (key) {
       seen.add(key);
     }
+    field.orderIndex = resolveOrderIndex(field);
     result.push(field);
   });
 
@@ -529,9 +550,15 @@ function mergeFieldDefinitionsWithValues(definitions, values) {
       return {
         ...field,
         value: field?.value ?? '',
+        orderIndex: resolveOrderIndex(field),
       };
     }
 
+    const resolvedOrder = Math.min(
+      resolveOrderIndex(field),
+      resolveOrderIndex(matchedValue.customField),
+    );
+
     return {
       ...field,
       customFieldValueId: matchedValue.id ?? field.customFieldValueId ?? null,
@@ -542,6 +569,7 @@ function mergeFieldDefinitionsWithValues(definitions, values) {
         null,
       customField: matchedValue.customField ?? field.customField ?? null,
       value: matchedValue.value ?? field.value ?? '',
+      orderIndex: resolvedOrder,
     };
   });
 
@@ -588,22 +616,31 @@ function mergeFieldDefinitionsWithValues(definitions, values) {
         options: entry.customField?.options ?? [],
         value: entry.value ?? '',
         customField: entry.customField ?? null,
+        orderIndex: resolveOrderIndex(entry.customField),
       });
     }
   });
 
-  return merged;
+  return merged.sort(
+    (a, b) => resolveOrderIndex(a) - resolveOrderIndex(b),
+  );
 }
 
 function dedupeMergedFields(fields) {
   if (!Array.isArray(fields) || fields.length <= 1) {
-    return Array.isArray(fields) ? fields : [];
+    return Array.isArray(fields)
+      ? fields.slice().sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b))
+      : [];
   }
 
   const seen = new Map();
   const result = [];
 
-  fields.forEach((field) => {
+  const orderedFields = fields
+    .slice()
+    .sort((a, b) => resolveOrderIndex(a) - resolveOrderIndex(b));
+
+  orderedFields.forEach((field) => {
     if (!field || typeof field !== 'object') {
       return;
     }
@@ -632,12 +669,14 @@ function dedupeMergedFields(fields) {
     const key = fieldId || nameKey;
 
     if (!key) {
+      field.orderIndex = resolveOrderIndex(field);
       result.push(field);
       return;
     }
 
     const existing = seen.get(key);
     if (!existing) {
+      field.orderIndex = resolveOrderIndex(field);
       seen.set(key, field);
       result.push(field);
       return;
@@ -654,11 +693,17 @@ function dedupeMergedFields(fields) {
 
     if (!existingHasValue && incomingHasValue) {
       Object.assign(existing, field);
+      existing.orderIndex = Math.min(
+        resolveOrderIndex(existing),
+        resolveOrderIndex(field),
+      );
       seen.set(key, existing);
     }
   });
 
-  return result;
+  return result.sort(
+    (a, b) => resolveOrderIndex(a) - resolveOrderIndex(b),
+  );
 }
 
 const pieceDefinitionSources = computed(() => {
diff --git a/app/components/PieceModelStructureEditor.vue b/app/components/PieceModelStructureEditor.vue
index bd01d10..47245ae 100644
--- a/app/components/PieceModelStructureEditor.vue
+++ b/app/components/PieceModelStructureEditor.vue
@@ -108,7 +108,7 @@ const extractRest = (structure = {}) => {
   )
 }
 
-const toEditorField = (input = {}) => ({
+const toEditorField = (input = {}, index = 0) => ({
   name: typeof input.name === 'string' ? input.name : '',
   type: typeof input.type === 'string' && input.type ? input.type : 'text',
   required: Boolean(input.required),
@@ -116,10 +116,14 @@ const toEditorField = (input = {}) => ({
     ? input.options.join('\n')
     : typeof input.optionsText === 'string'
       ? input.optionsText
-      : ''
+      : '',
+  orderIndex: typeof input.orderIndex === 'number' ? input.orderIndex : index,
 })
 
-const hydrateFields = (structure = {}) => ensureArray(structure.customFields).map(toEditorField)
+const hydrateFields = (structure = {}) =>
+  ensureArray(structure.customFields)
+    .map((field, index) => toEditorField(field, index))
+    .sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
 
 const localState = reactive({
   fields: hydrateFields(props.modelValue)
@@ -138,7 +142,7 @@ const localFields = computed({
 
 const normalizeFields = (fields) => {
   return ensureArray(fields)
-    .map((field) => {
+    .map((field, index) => {
       const name = typeof field.name === 'string' ? field.name.trim() : ''
       if (!name) {
         return null
@@ -156,7 +160,7 @@ const normalizeFields = (fields) => {
         options = parsed.length > 0 ? parsed : undefined
       }
 
-      const normalized = { name, type, required }
+      const normalized = { name, type, required, orderIndex: index }
       if (options) {
         normalized.options = options
       }
@@ -199,7 +203,8 @@ watch(
 watch(localFields, emitUpdate, { deep: true })
 
 const addField = () => {
-  localFields.value = [...localFields.value, toEditorField()]
+  const index = localFields.value.length
+  localFields.value = [...localFields.value, toEditorField({}, index)]
 }
 
 const removeField = (index) => {
diff --git a/app/components/StructureNodeEditor.vue b/app/components/StructureNodeEditor.vue
index bd2afbb..02499f4 100644
--- a/app/components/StructureNodeEditor.vue
+++ b/app/components/StructureNodeEditor.vue
@@ -79,9 +79,27 @@
             <div
               v-for="(field, index) in node.customFields"
               :key="`field-${index}`"
-              class="border border-base-200 rounded-md p-3 space-y-2"
+              class="border border-base-200 rounded-md p-3 space-y-2 transition-colors"
+              :class="customFieldReorderClass(index)"
+              draggable="true"
+              @dragstart="onCustomFieldDragStart(index, $event)"
+              @dragenter="onCustomFieldDragEnter(index)"
+              @dragover.prevent
+              @drop="onCustomFieldDrop(index)"
+              @dragend="onCustomFieldDragEnd"
             >
               <div class="flex items-start justify-between gap-2">
+                <div class="flex items-center gap-2">
+                  <button
+                    type="button"
+                    class="btn btn-ghost btn-xs btn-square cursor-grab active:cursor-grabbing"
+                    title="Réorganiser"
+                    draggable="true"
+                    @dragstart.stop="onCustomFieldDragStart(index, $event)"
+                  >
+                    <IconLucideGripVertical class="w-4 h-4" aria-hidden="true" />
+                  </button>
+                </div>
                 <div class="flex-1 space-y-2">
                   <div class="grid grid-cols-1 md:grid-cols-2 gap-2">
                     <input
@@ -506,20 +524,97 @@ const handlePieceTypeSelect = (piece: ComponentModelPiece & Record<string, any>)
   piece.typePieceLabel = formatPieceTypeOption(option)
 }
 
+const customFieldDragState = ref({
+  draggingIndex: null as number | null,
+  dropTargetIndex: null as number | null,
+})
+
+const reindexCustomFields = () => {
+  if (!Array.isArray(props.node.customFields)) {
+    return
+  }
+  props.node.customFields.forEach((field: any, index: number) => {
+    if (!field || typeof field !== 'object') {
+      return
+    }
+    field.orderIndex = index
+  })
+}
+
+const resetCustomFieldDragState = () => {
+  customFieldDragState.value.draggingIndex = null
+  customFieldDragState.value.dropTargetIndex = null
+}
+
+const onCustomFieldDragStart = (index: number, event: DragEvent) => {
+  customFieldDragState.value.draggingIndex = index
+  customFieldDragState.value.dropTargetIndex = index
+  if (event.dataTransfer) {
+    event.dataTransfer.effectAllowed = 'move'
+  }
+}
+
+const onCustomFieldDragEnter = (index: number) => {
+  if (customFieldDragState.value.draggingIndex === null) {
+    return
+  }
+  customFieldDragState.value.dropTargetIndex = index
+}
+
+const onCustomFieldDrop = (index: number) => {
+  if (!Array.isArray(props.node.customFields)) {
+    resetCustomFieldDragState()
+    return
+  }
+  const from = customFieldDragState.value.draggingIndex
+  const to = index
+  if (from === null || to === null) {
+    resetCustomFieldDragState()
+    return
+  }
+  moveItemInPlace(props.node.customFields, from, to)
+  reindexCustomFields()
+  resetCustomFieldDragState()
+}
+
+const onCustomFieldDragEnd = () => {
+  resetCustomFieldDragState()
+}
+
+const customFieldReorderClass = (index: number) => {
+  if (customFieldDragState.value.draggingIndex === index) {
+    return 'border-dashed border-primary'
+  }
+  if (
+    customFieldDragState.value.draggingIndex !== null &&
+    customFieldDragState.value.dropTargetIndex === index &&
+    customFieldDragState.value.draggingIndex !== index
+  ) {
+    return 'border-primary border-dashed bg-primary/5'
+  }
+  return ''
+}
+
 const addCustomField = () => {
   ensureArray('customFields')
+  const nextIndex = Array.isArray(props.node.customFields)
+    ? props.node.customFields.length
+    : 0
   props.node.customFields.push({
     name: '',
     type: 'text',
     required: false,
     optionsText: '',
     options: [],
+    orderIndex: nextIndex,
   })
+  reindexCustomFields()
 }
 
 const removeCustomField = (index: number) => {
   if (!Array.isArray(props.node.customFields)) return
   props.node.customFields.splice(index, 1)
+  reindexCustomFields()
 }
 
 const addPiece = () => {
@@ -723,6 +818,22 @@ watch(
   { deep: true }
 )
 
+watch(
+  () => props.node.customFields,
+  (value) => {
+    if (!Array.isArray(value)) {
+      return
+    }
+    value.sort((a: any, b: any) => {
+      const left = typeof a?.orderIndex === 'number' ? a.orderIndex : 0
+      const right = typeof b?.orderIndex === 'number' ? b.orderIndex : 0
+      return left - right
+    })
+    reindexCustomFields()
+  },
+  { deep: true }
+)
+
 watch(
   () => [props.lockedTypeLabel, props.lockType],
   () => {
diff --git a/app/components/TypeEditCustomFieldsSection.vue b/app/components/TypeEditCustomFieldsSection.vue
index b163158..b903937 100644
--- a/app/components/TypeEditCustomFieldsSection.vue
+++ b/app/components/TypeEditCustomFieldsSection.vue
@@ -24,11 +24,26 @@
       <div v-if="expanded" class="space-y-4">
         <div
           v-for="(field, fieldIndex) in fields"
-          :key="fieldIndex"
-          class="border border-gray-200 rounded-lg p-4 bg-gray-50"
+          :key="field.id || field.customFieldId || field.__key || `field-${fieldIndex}`"
+          class="border border-gray-200 rounded-lg p-4 bg-gray-50 transition-colors"
+          :class="fieldReorderClass(fieldIndex)"
+          draggable="true"
+          @dragstart="onFieldDragStart(fieldIndex, $event)"
+          @dragenter="onFieldDragEnter(fieldIndex)"
+          @dragover.prevent
+          @drop="onFieldDrop(fieldIndex)"
+          @dragend="onFieldDragEnd"
         >
           <div class="flex items-center justify-between mb-3">
             <div class="flex items-center gap-2">
+              <button
+                type="button"
+                class="btn btn-ghost btn-xs btn-square cursor-grab active:cursor-grabbing"
+                title="Réorganiser"
+                draggable="false"
+              >
+                <IconLucideGripVertical class="w-4 h-4" aria-hidden="true" />
+              </button>
               <button
                 type="button"
                 class="btn btn-ghost btn-xs p-1"
@@ -160,6 +175,7 @@ import IconLucideChevronRight from '~icons/lucide/chevron-right'
 import IconLucideListChecks from '~icons/lucide/list-checks'
 import IconLucideX from '~icons/lucide/x'
 import IconLucidePlus from '~icons/lucide/plus'
+import IconLucideGripVertical from '~icons/lucide/grip-vertical'
 
 const props = defineProps({
   modelValue: {
@@ -183,8 +199,57 @@ const fields = computed({
   set: value => emit('update:modelValue', value)
 })
 
+const createFieldKey = () => `cf-${Math.random().toString(16).slice(2)}-${Date.now()}`
+
 const expanded = ref(false)
 const expandedFields = ref([])
+const draggingFieldIndex = ref(null)
+const fieldDropTargetIndex = ref(null)
+
+const applyOrderIndex = (list = []) => {
+  if (!Array.isArray(list)) { return [] }
+  list.forEach((field, index) => {
+    if (field && typeof field === 'object') {
+      field.orderIndex = index
+      if (typeof field.__key !== 'string' || !field.__key) {
+        field.__key = createFieldKey()
+      }
+    }
+  })
+  return list
+}
+
+const createEmptyField = () => ({
+  name: '',
+  type: '',
+  required: false,
+  optionsText: '',
+  orderIndex: fields.value.length,
+  __key: createFieldKey()
+})
+
+const resetDragState = () => {
+  draggingFieldIndex.value = null
+  fieldDropTargetIndex.value = null
+}
+
+const reorderFields = (from, to) => {
+  const list = Array.isArray(fields.value) ? fields.value.slice() : []
+  if (from === to || from < 0 || to < 0 || from >= list.length || to >= list.length) {
+    resetDragState()
+    return
+  }
+  const [moved] = list.splice(from, 1)
+  list.splice(to, 0, moved)
+  if (Array.isArray(expandedFields.value)) {
+    const expandedCopy = expandedFields.value.slice()
+    const [expandedState] = expandedCopy.splice(from, 1)
+    expandedCopy.splice(to, 0, expandedState)
+    expandedFields.value = expandedCopy
+  }
+  fields.value = applyOrderIndex(list)
+  resetDragState()
+}
 
 watch(
   () => props.expandAllTrigger,
@@ -223,26 +288,25 @@ const toggleField = (index) => {
 }
 
 const addField = () => {
-  fields.value = [
-    ...fields.value,
-    {
-      name: '',
-      type: '',
-      required: false,
-      optionsText: ''
-    }
-  ]
+  const next = Array.isArray(fields.value) ? fields.value.slice() : []
+  next.push(createEmptyField())
+  fields.value = applyOrderIndex(next)
   expandedFields.value.push(true)
   expanded.value = true
 }
 
 const removeField = (index) => {
-  fields.value = fields.value.filter((_, i) => i !== index)
+  const next = Array.isArray(fields.value)
+    ? fields.value.filter((_, i) => i !== index)
+    : []
+  fields.value = applyOrderIndex(next)
   expandedFields.value.splice(index, 1)
 }
 
 const updateField = (index, patch) => {
-  fields.value = fields.value.map((field, i) => (i === index ? { ...field, ...patch } : field))
+  const next = Array.isArray(fields.value) ? fields.value.slice() : []
+  next[index] = { ...next[index], ...patch }
+  fields.value = applyOrderIndex(next)
 }
 
 const updateOptions = (index, value) => {
@@ -250,4 +314,43 @@ const updateOptions = (index, value) => {
     optionsText: value.replace(/\r\n/g, '\n').replace(/\r/g, '\n')
   })
 }
+
+const onFieldDragStart = (index, event) => {
+  draggingFieldIndex.value = index
+  fieldDropTargetIndex.value = index
+  if (event.dataTransfer) {
+    event.dataTransfer.effectAllowed = 'move'
+  }
+}
+
+const onFieldDragEnter = (index) => {
+  if (draggingFieldIndex.value === null) { return }
+  fieldDropTargetIndex.value = index
+}
+
+const onFieldDrop = (index) => {
+  if (draggingFieldIndex.value === null) {
+    resetDragState()
+    return
+  }
+  reorderFields(draggingFieldIndex.value, index)
+}
+
+const onFieldDragEnd = () => {
+  resetDragState()
+}
+
+const fieldReorderClass = (index) => {
+  if (draggingFieldIndex.value === index) {
+    return 'border-dashed border-primary'
+  }
+  if (
+    draggingFieldIndex.value !== null &&
+    fieldDropTargetIndex.value === index &&
+    draggingFieldIndex.value !== index
+  ) {
+    return 'border-primary border-dashed bg-primary/5'
+  }
+  return ''
+}
 </script>
diff --git a/app/components/TypeEditForm.vue b/app/components/TypeEditForm.vue
index 9bab4c5..33f1ec0 100644
--- a/app/components/TypeEditForm.vue
+++ b/app/components/TypeEditForm.vue
@@ -54,14 +54,33 @@ const emit = defineEmits(['update:modelValue', 'submit'])
 
 const deepClone = value => JSON.parse(JSON.stringify(value))
 
+const createFieldKey = () => `cf-${Math.random().toString(16).slice(2)}-${Date.now()}`
+
+const withNormalizedOrder = (items = []) => {
+  if (!Array.isArray(items)) { return [] }
+  return items
+    .map((item, index) => {
+      const clone = deepClone(item)
+      const currentOrder =
+        typeof clone?.orderIndex === 'number' ? clone.orderIndex : index
+      clone.orderIndex = currentOrder
+      if (typeof clone?.__key !== 'string' || !clone.__key) {
+        clone.__key = createFieldKey()
+      }
+      return clone
+    })
+    .sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
+    .map((item, index) => ({ ...item, orderIndex: index }))
+}
+
 const createDefaultForm = (source = {}) => ({
   name: source.name || '',
   description: source.description || '',
   category: source.category || '',
   maintenanceFrequency: source.maintenanceFrequency || '',
-  customFields: deepClone(source.customFields || []),
-  componentRequirements: deepClone(source.componentRequirements || []),
-  pieceRequirements: deepClone(source.pieceRequirements || [])
+  customFields: withNormalizedOrder(source.customFields || []),
+  componentRequirements: withNormalizedOrder(source.componentRequirements || []),
+  pieceRequirements: withNormalizedOrder(source.pieceRequirements || [])
 })
 
 const formData = reactive(createDefaultForm(props.modelValue))
diff --git a/app/pages/component/[id]/edit.vue b/app/pages/component/[id]/edit.vue
index e57fa7c..d503b67 100644
--- a/app/pages/component/[id]/edit.vue
+++ b/app/pages/component/[id]/edit.vue
@@ -424,6 +424,7 @@ interface CustomFieldInput {
   value: string
   customFieldId: string | null
   customFieldValueId: string | null
+  orderIndex: number
 }
 
 const route = useRoute()
@@ -756,6 +757,7 @@ const buildCustomFieldInputs = (
         ...definition,
         customFieldId: definition.customFieldId || definition.id,
         customFieldValueId: null,
+        orderIndex: definition.orderIndex,
       }
     }
 
@@ -765,8 +767,14 @@ const buildCustomFieldInputs = (
       customFieldId: matched.customField?.id || definition.customFieldId || definition.id,
       customFieldValueId: matched.id ?? null,
       value: formatDefaultValue(definition.type, resolvedValue),
+      orderIndex: Math.min(
+        definition.orderIndex ?? 0,
+        typeof matched.customField?.orderIndex === 'number'
+          ? matched.customField.orderIndex
+          : definition.orderIndex ?? 0,
+      ),
     }
-  })
+  }).sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
 
   return resolved
 }
@@ -780,11 +788,12 @@ const normalizeCustomFieldInputs = (structure: ComponentModelStructure | null):
   }
   const fields = Array.isArray(structure.customFields) ? structure.customFields : []
   return fields
-    .map((field) => normalizeCustomField(field))
+    .map((field, index) => normalizeCustomField(field, index))
     .filter((field): field is CustomFieldInput => field !== null)
+    .sort((a, b) => a.orderIndex - b.orderIndex)
 }
 
-const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
+const normalizeCustomField = (rawField: any, fallbackIndex = 0): CustomFieldInput | null => {
   if (!rawField || typeof rawField !== 'object') {
     return null
   }
@@ -802,7 +811,8 @@ const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
   const customFieldValueId = typeof rawField.customFieldValueId === 'string'
     ? rawField.customFieldValueId
     : null
-  return { id, name, type, required, options, value, customFieldId, customFieldValueId }
+  const orderIndex = typeof rawField.orderIndex === 'number' ? rawField.orderIndex : fallbackIndex
+  return { id, name, type, required, options, value, customFieldId, customFieldValueId, orderIndex }
 }
 
 const resolveFieldName = (field: any): string => {
diff --git a/app/pages/component/create.vue b/app/pages/component/create.vue
index e381119..2d1bc6a 100644
--- a/app/pages/component/create.vue
+++ b/app/pages/component/create.vue
@@ -841,6 +841,7 @@ interface CustomFieldInput {
   value: string
   customFieldId: string | null
   customFieldValueId: string | null
+  orderIndex: number
 }
 
 const fieldKey = (field: CustomFieldInput, index: number) =>
@@ -852,11 +853,12 @@ const normalizeCustomFieldInputs = (structure: ComponentModelStructure | null):
   }
   const fields = Array.isArray(structure.customFields) ? structure.customFields : []
   return fields
-    .map((field) => normalizeCustomField(field))
+    .map((field, index) => normalizeCustomField(field, index))
     .filter((field): field is CustomFieldInput => field !== null)
+    .sort((a, b) => a.orderIndex - b.orderIndex)
 }
 
-const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
+const normalizeCustomField = (rawField: any, fallbackIndex = 0): CustomFieldInput | null => {
   if (!rawField || typeof rawField !== 'object') {
     return null
   }
@@ -874,7 +876,8 @@ const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
   const customFieldValueId = typeof rawField.customFieldValueId === 'string'
     ? rawField.customFieldValueId
     : null
-  return { id, name, type, required, options, value, customFieldId, customFieldValueId }
+  const orderIndex = typeof rawField.orderIndex === 'number' ? rawField.orderIndex : fallbackIndex
+  return { id, name, type, required, options, value, customFieldId, customFieldValueId, orderIndex }
 }
 
 const resolveFieldName = (field: any): string => {
diff --git a/app/pages/machine-skeleton/new.vue b/app/pages/machine-skeleton/new.vue
index 49dc61b..26112cd 100644
--- a/app/pages/machine-skeleton/new.vue
+++ b/app/pages/machine-skeleton/new.vue
@@ -139,12 +139,15 @@ const parseOptions = (field = {}) => {
 const normalizeCustomFields = (fields = []) =>
   fields
     .filter(field => field?.name && field.name.trim() !== '')
-    .map(field => ({
+    .map((field, index) => ({
       name: field.name,
       type: field.type || '',
       required: !!field.required,
-      options: parseOptions(field)
+      options: parseOptions(field),
+      orderIndex: typeof field.orderIndex === 'number' ? field.orderIndex : index
     }))
+    .sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
+    .map((field, index) => ({ ...field, orderIndex: index }))
 
 const toIntegerOrNull = (value, fallback = null) => {
   if (value === '' || value === undefined || value === null) {
diff --git a/app/pages/machine/[id].vue b/app/pages/machine/[id].vue
index a5f0d54..4fdb4c8 100644
--- a/app/pages/machine/[id].vue
+++ b/app/pages/machine/[id].vue
@@ -1853,6 +1853,12 @@ const visibleMachineCustomFields = computed(() => {
 const summarizeCustomFields = (fields = []) => {
   const seen = new Set()
   return fields
+    .slice()
+    .sort((a, b) => {
+      const left = typeof a?.orderIndex === 'number' ? a.orderIndex : 0
+      const right = typeof b?.orderIndex === 'number' ? b.orderIndex : 0
+      return left - right
+    })
     .filter(shouldDisplayCustomField)
     .filter((field) => {
       const key = field.customFieldId || field.id || field.name
@@ -2013,11 +2019,12 @@ const normalizeExistingCustomFieldDefinitions = (fields) => {
     return []
   }
   return fields
-    .map((field) => normalizeCustomFieldDefinitionEntry(field))
+    .map((field, index) => normalizeCustomFieldDefinitionEntry(field, index))
     .filter((definition) => definition !== null)
+    .sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
 }
 
-const normalizeCustomFieldDefinitionEntry = (definition = {}) => {
+const normalizeCustomFieldDefinitionEntry = (definition = {}, fallbackIndex = 0) => {
   const name = extractDefinitionName(definition)
   if (!name) {
     return null
@@ -2028,6 +2035,7 @@ const normalizeCustomFieldDefinitionEntry = (definition = {}) => {
   const defaultValue = extractDefinitionDefaultValue(definition)
   const id = typeof definition?.id === 'string' ? definition.id : undefined
   const customFieldId = typeof definition?.customFieldId === 'string' ? definition.customFieldId : id
+  const orderIndex = typeof definition?.orderIndex === 'number' ? definition.orderIndex : fallbackIndex
   return {
     id,
     customFieldId,
@@ -2037,6 +2045,7 @@ const normalizeCustomFieldDefinitionEntry = (definition = {}) => {
     options,
     defaultValue,
     readOnly: !!definition?.readOnly,
+    orderIndex,
   }
 }
 
diff --git a/app/pages/pieces/[id]/edit.vue b/app/pages/pieces/[id]/edit.vue
index 3e0fd9b..ce2e891 100644
--- a/app/pages/pieces/[id]/edit.vue
+++ b/app/pages/pieces/[id]/edit.vue
@@ -383,6 +383,7 @@ interface CustomFieldInput {
   value: string
   customFieldId: string | null
   customFieldValueId: string | null
+  orderIndex: number
 }
 
 const route = useRoute()
@@ -706,6 +707,7 @@ const buildCustomFieldInputs = (
         ...definition,
         customFieldId: definition.customFieldId || definition.id,
         customFieldValueId: null,
+        orderIndex: definition.orderIndex,
       }
     }
 
@@ -715,8 +717,14 @@ const buildCustomFieldInputs = (
       customFieldId: matched.customField?.id || definition.customFieldId || definition.id,
       customFieldValueId: matched.id ?? null,
       value: formatDefaultValue(definition.type, resolvedValue),
+      orderIndex: Math.min(
+        definition.orderIndex ?? 0,
+        typeof matched.customField?.orderIndex === 'number'
+          ? matched.customField.orderIndex
+          : definition.orderIndex ?? 0,
+      ),
     }
-  })
+  }).sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
 
   return resolved
 }
@@ -730,11 +738,12 @@ const normalizeCustomFieldInputs = (structure: PieceModelStructure | null): Cust
   }
   const fields = Array.isArray(structure.customFields) ? structure.customFields : []
   return fields
-    .map((field) => normalizeCustomField(field))
+    .map((field, index) => normalizeCustomField(field, index))
     .filter((field): field is CustomFieldInput => field !== null)
+    .sort((a, b) => a.orderIndex - b.orderIndex)
 }
 
-const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
+const normalizeCustomField = (rawField: any, fallbackIndex = 0): CustomFieldInput | null => {
   if (!rawField || typeof rawField !== 'object') {
     return null
   }
@@ -755,7 +764,9 @@ const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
     ? rawField.customFieldValueId
     : null
 
-  return { id, name, type, required, options, value, customFieldId, customFieldValueId }
+  const orderIndex = typeof rawField.orderIndex === 'number' ? rawField.orderIndex : fallbackIndex
+
+  return { id, name, type, required, options, value, customFieldId, customFieldValueId, orderIndex }
 }
 
 const resolveFieldName = (field: any): string => {
diff --git a/app/pages/pieces/create.vue b/app/pages/pieces/create.vue
index ec2437b..7952368 100644
--- a/app/pages/pieces/create.vue
+++ b/app/pages/pieces/create.vue
@@ -467,6 +467,7 @@ interface CustomFieldInput {
   value: string
   customFieldId: string | null
   customFieldValueId: string | null
+  orderIndex: number
 }
 
 const fieldKey = (field: CustomFieldInput, index: number) =>
@@ -478,11 +479,12 @@ const normalizeCustomFieldInputs = (structure: PieceModelStructure | null): Cust
   }
   const fields = Array.isArray(structure.customFields) ? structure.customFields : []
   return fields
-    .map((field) => normalizeCustomField(field))
+    .map((field, index) => normalizeCustomField(field, index))
     .filter((field): field is CustomFieldInput => field !== null)
+    .sort((a, b) => a.orderIndex - b.orderIndex)
 }
 
-const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
+const normalizeCustomField = (rawField: any, fallbackIndex = 0): CustomFieldInput | null => {
   if (!rawField || typeof rawField !== 'object') {
     return null
   }
@@ -503,7 +505,9 @@ const normalizeCustomField = (rawField: any): CustomFieldInput | null => {
     ? rawField.customFieldValueId
     : null
 
-  return { id, name, type, required, options, value, customFieldId, customFieldValueId }
+  const orderIndex = typeof rawField.orderIndex === 'number' ? rawField.orderIndex : fallbackIndex
+
+  return { id, name, type, required, options, value, customFieldId, customFieldValueId, orderIndex }
 }
 
 const resolveFieldName = (field: any): string => {
diff --git a/app/pages/type/edit/[id].vue b/app/pages/type/edit/[id].vue
index 15cc7f4..dcaba98 100644
--- a/app/pages/type/edit/[id].vue
+++ b/app/pages/type/edit/[id].vue
@@ -92,12 +92,15 @@ const parseOptions = (field = {}) => {
 const normalizeCustomFields = (fields = []) =>
   fields
     .filter(field => field?.name && field.name.trim() !== '')
-    .map(field => ({
+    .map((field, index) => ({
       name: field.name,
       type: field.type || '',
       required: !!field.required,
-      options: parseOptions(field)
+      options: parseOptions(field),
+      orderIndex: typeof field.orderIndex === 'number' ? field.orderIndex : index
     }))
+    .sort((a, b) => (a.orderIndex ?? 0) - (b.orderIndex ?? 0))
+    .map((field, index) => ({ ...field, orderIndex: index }))
 
 const toIntegerOrNull = (value, fallback = null) => {
   if (value === '' || value === undefined || value === null) {
diff --git a/app/shared/modelUtils.ts b/app/shared/modelUtils.ts
index 68d6025..fbe1522 100644
--- a/app/shared/modelUtils.ts
+++ b/app/shared/modelUtils.ts
@@ -94,7 +94,7 @@ const sanitizeCustomFields = (fields: any[]): ComponentModelCustomField[] => {
   }
 
   return fields
-    .map((field) => {
+    .map((field, index) => {
       const rawName =
         typeof field?.name === 'string'
           ? field.name
@@ -173,6 +173,8 @@ const sanitizeCustomFields = (fields: any[]): ComponentModelCustomField[] => {
       if (customFieldId) {
         result.customFieldId = customFieldId
       }
+      const orderIndex = typeof field?.orderIndex === 'number' ? field.orderIndex : index
+      result.orderIndex = orderIndex
       return result
     })
     .filter((field): field is ComponentModelCustomField => !!field)
@@ -448,7 +450,7 @@ const hydrateCustomFields = (fields: any[]): any[] => {
     return []
   }
 
-  return fields.map((field) => {
+  return fields.map((field, index) => {
     const valueObject = extractFieldValueObject(field)
     const name = typeof field?.name === 'string'
       ? field.name
@@ -513,6 +515,7 @@ const hydrateCustomFields = (fields: any[]): any[] => {
 
     const id = typeof field?.id === 'string' ? field.id : undefined
     const customFieldId = typeof field?.customFieldId === 'string' ? field.customFieldId : undefined
+    const orderIndex = typeof field?.orderIndex === 'number' ? field.orderIndex : index
 
     return {
       name,
@@ -523,6 +526,7 @@ const hydrateCustomFields = (fields: any[]): any[] => {
       defaultValue,
       id,
       customFieldId,
+      orderIndex,
     }
   })
 }
@@ -580,7 +584,7 @@ const mapComponentCustomFields = (fields: any[]) => {
   if (!Array.isArray(fields)) {
     return []
   }
-  return hydrateCustomFields(fields).map((field) => {
+  return hydrateCustomFields(fields).map((field, index) => {
     const defaultValue =
       field?.defaultValue !== undefined && field?.defaultValue !== null && field?.defaultValue !== ''
         ? field.defaultValue
@@ -597,6 +601,7 @@ const mapComponentCustomFields = (fields: any[]) => {
         typeof (field as any)?.customFieldId === 'string'
           ? (field as any).customFieldId
           : undefined,
+      orderIndex: typeof field?.orderIndex === 'number' ? field.orderIndex : index,
     }
   })
 }
@@ -772,7 +777,7 @@ const sanitizePieceCustomFields = (fields: any[]): PieceModelCustomField[] => {
   }
 
   return fields
-    .map((field) => {
+    .map((field, index) => {
       const name = typeof field?.name === 'string' ? field.name.trim() : ''
       if (!name) {
         return null
@@ -799,6 +804,8 @@ const sanitizePieceCustomFields = (fields: any[]): PieceModelCustomField[] => {
       if (options) {
         result.options = options
       }
+      const orderIndex = typeof field?.orderIndex === 'number' ? field.orderIndex : index
+      result.orderIndex = orderIndex
       return result
     })
     .filter((field): field is PieceModelCustomField => !!field)
@@ -819,7 +826,7 @@ const hydratePieceCustomFields = (fields: any[]): PieceModelStructureEditorField
     return []
   }
 
-  return fields.map((field) => ({
+  return fields.map((field, index) => ({
     name: field?.name ?? '',
     type: field?.type ?? 'text',
     required: !!field?.required,
@@ -829,6 +836,7 @@ const hydratePieceCustomFields = (fields: any[]): PieceModelStructureEditorField
       : Array.isArray(field?.options)
         ? field.options.join('\n')
         : '',
+    orderIndex: typeof field?.orderIndex === 'number' ? field.orderIndex : index,
   }))
 }
 
diff --git a/app/shared/types/inventory.ts b/app/shared/types/inventory.ts
index c09546e..d842b5b 100644
--- a/app/shared/types/inventory.ts
+++ b/app/shared/types/inventory.ts
@@ -9,6 +9,7 @@ export interface ComponentModelCustomField {
   optionsText?: string
   id?: string
   customFieldId?: string
+  orderIndex?: number
 }
 
 export interface ComponentModelPiece {
@@ -40,6 +41,7 @@ export interface PieceModelCustomField {
   type: PieceModelCustomFieldType
   required: boolean
   options?: string[]
+  orderIndex?: number
 }
 
 export interface PieceModelStructure {