diff --git a/api/manage_workflows.php b/api/manage_workflows.php
index 90ba6dd..9ce5c6e 100644
--- a/api/manage_workflows.php
+++ b/api/manage_workflows.php
@@ -97,13 +97,39 @@ try {
                 exit;
             }
 
+            $wf_active  = (int)($data['is_active'] ?? 1);
+
+            // status_transitions already has a DB-level UNIQUE KEY on
+            // (from_status, to_status) (regardless of is_active), so a
+            // duplicate pair can't actually be inserted — but hitting that
+            // constraint raw surfaces as an opaque "internal error occurred"
+            // to the admin instead of a clear message. Check first so the
+            // common case (an admin re-adding a pair that already exists)
+            // gets a friendly, specific error.
+            $dupCheck = $conn->prepare(
+                "SELECT transition_id FROM status_transitions WHERE from_status = ? AND to_status = ?"
+            );
+            $dupCheck->bind_param('ss', $data['from_status'], $data['to_status']);
+            $dupCheck->execute();
+            if ($dupCheck->get_result()->fetch_assoc()) {
+                $dupCheck->close();
+                http_response_code(409);
+                echo json_encode([
+                    'success' => false,
+                    'error' => 'A transition already exists for '
+                        . $data['from_status'] . ' → ' . $data['to_status']
+                        . ' — edit that row instead of creating a duplicate.',
+                ]);
+                exit;
+            }
+            $dupCheck->close();
+
             $stmt = $conn->prepare("INSERT INTO status_transitions (from_status, to_status, requires_comment, requires_admin, is_active)
                                     VALUES (?, ?, ?, ?, ?)");
             $wf_from    = $data['from_status'];
             $wf_to      = $data['to_status'];
             $wf_comment = (int)($data['requires_comment'] ?? 0);
             $wf_admin   = (int)($data['requires_admin'] ?? 0);
-            $wf_active  = (int)($data['is_active'] ?? 1);
             $stmt->bind_param('ssiii', $wf_from, $wf_to, $wf_comment, $wf_admin, $wf_active);
 
             if ($stmt->execute()) {
@@ -149,6 +175,28 @@ try {
                 exit;
             }
 
+            $wf_active  = (int)($data['is_active'] ?? 1);
+
+            // Same duplicate-pair guard as create, excluding this row itself.
+            $dupCheck = $conn->prepare(
+                "SELECT transition_id FROM status_transitions
+                 WHERE from_status = ? AND to_status = ? AND transition_id != ?"
+            );
+            $dupCheck->bind_param('ssi', $data['from_status'], $data['to_status'], $id);
+            $dupCheck->execute();
+            if ($dupCheck->get_result()->fetch_assoc()) {
+                $dupCheck->close();
+                http_response_code(409);
+                echo json_encode([
+                    'success' => false,
+                    'error' => 'A transition already exists for '
+                        . $data['from_status'] . ' → ' . $data['to_status']
+                        . ' — edit that row instead of creating a duplicate.',
+                ]);
+                exit;
+            }
+            $dupCheck->close();
+
             $stmt = $conn->prepare("UPDATE status_transitions SET
                                     from_status = ?, to_status = ?, requires_comment = ?, requires_admin = ?, is_active = ?
                                     WHERE transition_id = ?");
@@ -156,7 +204,6 @@ try {
             $wf_to      = $data['to_status'];
             $wf_comment = (int)($data['requires_comment'] ?? 0);
             $wf_admin   = (int)($data['requires_admin'] ?? 0);
-            $wf_active  = (int)($data['is_active'] ?? 1);
             $stmt->bind_param('ssiiii', $wf_from, $wf_to, $wf_comment, $wf_admin, $wf_active, $id);
 
             $success = $stmt->execute();
diff --git a/models/WorkflowModel.php b/models/WorkflowModel.php
index 473bfed..7928871 100644
--- a/models/WorkflowModel.php
+++ b/models/WorkflowModel.php
@@ -31,9 +31,15 @@ class WorkflowModel
             return $cached;
         }
 
+        // ORDER BY makes which row wins deterministic (most recently created,
+        // by transition_id) in the pathological case where two active rows
+        // exist for the same (from_status, to_status) pair — manage_workflows.php
+        // now rejects creating that duplicate going forward, but this is a
+        // defense-in-depth backstop against any duplicate already in the DB.
         $sql = "SELECT from_status, to_status, requires_comment, requires_admin
                 FROM status_transitions
-                WHERE is_active = TRUE";
+                WHERE is_active = TRUE
+                ORDER BY transition_id ASC";
         $result = $this->conn->query($sql);
 
         if (!$result) {