diff --git a/frontend/src/pages/ProceduralEditorPage.tsx b/frontend/src/pages/ProceduralEditorPage.tsx
index b1c6a73e..511dfc0b 100644
--- a/frontend/src/pages/ProceduralEditorPage.tsx
+++ b/frontend/src/pages/ProceduralEditorPage.tsx
@@ -13,10 +13,13 @@ import { TagInput } from '@/components/common/TagInput'
 import { Spinner } from '@/components/common/Spinner'
 import { EditorAIPanel } from '@/components/editor-ai/EditorAIPanel'
 import { ContextMenu } from '@/components/common/ContextMenu'
+import { ValidationSummary } from '@/components/tree-editor/ValidationSummary'
+import { AIFixReviewModal } from '@/components/tree-editor/AIFixReviewModal'
 import { useEditorAI } from '@/hooks/useEditorAI'
 import { cn } from '@/lib/utils'
 import { toast } from '@/lib/toast'
-import type { TreeType, MaintenanceSchedule, TargetList, ProceduralStep, IntakeFormField } from '@/types'
+import type { TreeType, MaintenanceSchedule, TargetList, ProceduralStep, IntakeFormField, AIFixProposal } from '@/types'
+import type { ValidationError } from '@/store/treeEditorStore'
 
 type SectionKey = 'details' | 'intake' | 'schedule'
 
@@ -51,6 +54,9 @@ export function ProceduralEditorPage() {
   } = useProceduralEditorStore()
 
   const steps = useProceduralEditorStore(s => s.steps)
+  const validationErrors = useProceduralEditorStore((s) => s.validationErrors)
+  const setExpandedStepId = useProceduralEditorStore((s) => s.setExpandedStepId)
+  const updateStep = useProceduralEditorStore((s) => s.updateStep)
 
   const handleFlowUpdate = useCallback((workingTree: Record<string, unknown>, metadata?: Record<string, unknown> | null) => {
     const stepsData = workingTree.steps as ProceduralStep[] | undefined
@@ -75,6 +81,9 @@ export function ProceduralEditorPage() {
     onFlowUpdate: handleFlowUpdate,
   })
 
+  const [isFixing, setIsFixing] = useState(false)
+  const [fixProposals, setFixProposals] = useState<AIFixProposal[] | null>(null)
+
   const isMaintenance = treeType === 'maintenance'
   const flowLabel = isMaintenance ? 'Maintenance Flow' : 'Procedure'
 
@@ -110,6 +119,10 @@ export function ProceduralEditorPage() {
     return () => { reset() }
   }, [id])
 
+  useEffect(() => {
+    useProceduralEditorStore.getState().validate()
+  }, [steps, intakeForm])
+
   const loadExistingTree = async (treeId: string) => {
     try {
       const tree = await treesApi.get(treeId)
@@ -125,12 +138,77 @@ export function ProceduralEditorPage() {
     }
   }
 
+  const handleSelectStep = useCallback((stepId: string) => {
+    // Guard against setExpandedStepId's toggle behavior — calling it with the same ID collapses the step
+    const currentExpanded = useProceduralEditorStore.getState().expandedStepId
+    if (currentExpanded !== stepId) {
+      setExpandedStepId(stepId)
+    }
+    // Small delay to let expanded state render before scrolling
+    setTimeout(() => {
+      const el = document.querySelector(`[data-step-id="${stepId}"]`)
+      if (el) el.scrollIntoView({ behavior: 'smooth', block: 'center' })
+    }, 50)
+  }, [setExpandedStepId])
+
+  const handleFixWithAI = async () => {
+    const fixableErrors = validationErrors
+      .filter((e) => e.severity === 'error' && e.stepId)
+      .map((e) => ({ node_id: e.stepId!, message: e.message }))
+
+    if (fixableErrors.length === 0) return
+
+    setIsFixing(true)
+    try {
+      const result = await treesApi.fixTree({
+        tree_structure: { steps } as unknown as Record<string, unknown>,
+        tree_name: name,
+        tree_type: treeType as 'procedural' | 'maintenance',
+        validation_errors: fixableErrors,
+      })
+      if (result.fixes.length > 0) {
+        setFixProposals(result.fixes)
+      } else {
+        toast.info('AI could not generate fixes for these errors')
+      }
+    } catch {
+      toast.error('Failed to generate AI fixes. Please try again.')
+    } finally {
+      setIsFixing(false)
+    }
+  }
+
+  const handleApplyFix = (fix: AIFixProposal) => {
+    updateStep(fix.target_node_id, fix.fixed_node as Partial<ProceduralStep>)
+    useProceduralEditorStore.getState().validate()
+  }
+
+  // AIFixReviewModal.onApplyAll is () => void — no arguments
+  const handleApplyAllFixes = () => {
+    if (!fixProposals) return
+    fixProposals.forEach((fix) => {
+      updateStep(fix.target_node_id, fix.fixed_node as Partial<ProceduralStep>)
+    })
+    useProceduralEditorStore.getState().validate()
+    setFixProposals(null)
+  }
+
+  const handleCloseFixModal = () => setFixProposals(null)
+
   const handleSave = async (saveStatus?: 'draft' | 'published') => {
     if (!name.trim()) {
       toast.error(`Please enter a name for the ${flowLabel.toLowerCase()}`)
       return
     }
 
+    // Block publish if there are validation errors
+    const errors = useProceduralEditorStore.getState().validate()
+    const hasErrors = errors.some((e) => e.severity === 'error')
+    if (hasErrors && saveStatus === 'published') {
+      toast.error('Please fix all errors before publishing')
+      return
+    }
+
     setIsSaving(true)
     try {
       const payload = getTreeForSave()
@@ -319,6 +397,21 @@ export function ProceduralEditorPage() {
 
       {/* Step List */}
       <div className="min-h-0 flex-1 overflow-y-auto px-4 py-4">
+        {validationErrors.length > 0 && (
+          <div className="px-4 py-3">
+            <ValidationSummary
+              errors={validationErrors.map((e): ValidationError => ({
+                nodeId: e.stepId,
+                field: e.field,
+                message: e.message,
+                severity: e.severity,
+              }))}
+              onSelectNode={handleSelectStep}
+              onFixWithAI={handleFixWithAI}
+              isFixing={isFixing}
+            />
+          </div>
+        )}
         <StepList onStepContextMenu={editorAI.openContextMenu} />
       </div>
 
@@ -366,6 +459,15 @@ export function ProceduralEditorPage() {
         isLoading={editorAI.isLoading}
         suggestions={editorAI.suggestions}
       />
+
+      {fixProposals && (
+        <AIFixReviewModal
+          fixes={fixProposals}
+          onApply={handleApplyFix}
+          onApplyAll={handleApplyAllFixes}
+          onClose={handleCloseFixModal}
+        />
+      )}
     </div>
   )
 }