diff --git a/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Stagelet.java b/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Stagelet.java
index 594fcae..68b2cad 100644
--- a/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Stagelet.java
+++ b/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Stagelet.java
@@ -231,7 +231,7 @@
     }
 
     @Override
-    public ICounter getCounter(String name, boolean create) {
+    public synchronized ICounter getCounter(String name, boolean create) {
         Counter counter = counterMap.get(name);
         if (counter == null && create) {
             counter = new Counter(name);