diff --git a/catalog/aws/singer-taps/step-functions.tf b/catalog/aws/singer-taps/step-functions.tf
index 2cd2284e..4950a033 100644
--- a/catalog/aws/singer-taps/step-functions.tf
+++ b/catalog/aws/singer-taps/step-functions.tf
@@ -6,8 +6,32 @@ locals {
   "Version": "1.0",
   "Comment": "Run Sync (ECS Fargate: ${tap_spec.image})",
   "TimeoutSeconds": ${var.timeout_hours * (60 * 60)},
-  "StartAt": "RunTask",
+  "StartAt": "ListRunningExecutions",
   "States": {
+    "ListRunningExecutions": {
+      "Type": "Task",
+      "Parameters": {
+        "StateMachineArn.$": "$$.StateMachine.Id",
+        "StatusFilter": "RUNNING"
+      },
+      "Resource": "arn:aws:states:::aws-sdk:sfn:listExecutions",
+      "Next": "IsExecutionCountGreaterThan1",
+      "ResultPath": "$.runningExecutionsCount",
+      "ResultSelector": {
+        "runningExecutionsCount.$": "States.ArrayLength($.Executions)"
+      }
+    },
+    "IsExecutionCountGreaterThan1": {
+      "Type": "Choice",
+      "Choices": [
+        {
+          "Variable": "$.runningExecutionsCount.runningExecutionsCount",
+          "NumericGreaterThan": 1,
+          "Next": "NotifyOnError"
+        }
+      ],
+      "Default": "RunTask"
+    },
     "RunTask": {
       "Type": "Task",
       "Resource": "arn:aws:states:::ecs:runTask.sync",