Index: src/components/org/apache/jmeter/control/InterleaveControl.java
===================================================================
--- src/components/org/apache/jmeter/control/InterleaveControl.java	(revision 1761202)
+++ src/components/org/apache/jmeter/control/InterleaveControl.java	(working copy)
@@ -19,18 +19,80 @@
 package org.apache.jmeter.control;
 
 import java.io.Serializable;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReadWriteLock;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 import org.apache.jmeter.samplers.Sampler;
 import org.apache.jmeter.testelement.TestElement;
+import org.apache.jmeter.testelement.TestStateListener;
+import org.apache.jmeter.testelement.property.BooleanProperty;
 import org.apache.jmeter.testelement.property.IntegerProperty;
 
 /**
  * Alternate among each of the children controllers or samplers for each loop iteration
  */
-public class InterleaveControl extends GenericController implements Serializable {
-    private static final long serialVersionUID = 233L;
+public class InterleaveControl extends GenericController implements Serializable, TestStateListener {
+    
+    public static final class SafeCounter {
+        private ReadWriteLock rwlock = new ReentrantReadWriteLock();
+
+        private Lock rlock = rwlock.readLock();
+        private Lock wlock = rwlock.writeLock();
+
+        private AtomicBoolean initialized = new AtomicBoolean();
+        private int maxValue;
+        private int counter;
+        
+        public SafeCounter() {
+        }
+
+        public int getCounter() {
+            try {
+                rlock.lock();
+                return counter;
+            } finally {
+                rlock.unlock();
+            }
+        }
+
+        public int getAndIncrement() {
+            int result;
+            try {
+                wlock.lock();
+                result = counter++;
+                if(counter == maxValue) {
+                    counter = 0;
+                }
+                return result;
+            } finally {
+                wlock.unlock();
+            }
+        }
+
+        public void initIfNeeded(int maxValue) {
+            try {
+                wlock.lock();
+                if(initialized.compareAndSet(false, true)) {
+                    this.maxValue = maxValue;
+                }
+            } finally {
+                wlock.unlock();
+            }
+        }
+        
+        public void reset() {
+            this.counter = 0;
+            this.initialized.set(false);
+        }
+    }
+    
+    private static final long serialVersionUID = 234L;
 
     private static final String STYLE = "InterleaveControl.style";// $NON-NLS-1$
+    
+    private static final String ACCROSS_THREADS = "InterleaveControl.accrossThreads";// $NON-NLS-1$
 
     public static final int IGNORE_SUB_CONTROLLERS = 0;
 
@@ -43,11 +105,16 @@
     private boolean currentReturnedAtLeastOne;
 
     private boolean stillSame = true;
+    
+    private transient SafeCounter sharedCounter = new SafeCounter();
+
+    private transient boolean interleaveAccrossThreads;
 
     /***************************************************************************
      * Constructor for the InterleaveControl object
      **************************************************************************/
     public InterleaveControl() {
+        super();
     }
 
     /**
@@ -71,6 +138,14 @@
     public int getStyle() {
         return getPropertyAsInt(STYLE);
     }
+    
+    public void setInterleaveAccrossThreads(boolean accrossThreads) {
+        setProperty(new BooleanProperty(ACCROSS_THREADS, accrossThreads));
+    }
+
+    public boolean getInterleaveAccrossThreads() {
+        return getPropertyAsBoolean(ACCROSS_THREADS, false);
+    }
 
     /**
      * {@inheritDoc}
@@ -172,6 +247,52 @@
             skipNext = true;
         }
         stillSame = false;
-        super.incrementCurrent();
+        if(!interleaveAccrossThreads) {
+            current = sharedCounter.getAndIncrement();
+        } else {
+            super.incrementCurrent();            
+        }
+    }
+    
+    @Override
+    public Object clone() {
+        InterleaveControl clone = (InterleaveControl) super.clone();
+        // Share the counter among threads
+        clone.sharedCounter = sharedCounter;
+        return clone;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.jmeter.control.GenericController#initialize()
+     */
+    @Override
+    public void initialize() {
+        super.initialize();
+        sharedCounter.initIfNeeded(getSubControllers().size());
+        interleaveAccrossThreads = getInterleaveAccrossThreads();
+        // get a different start index
+        if(interleaveAccrossThreads) {
+            this.current = sharedCounter.getAndIncrement();
+        }
+    }
+
+    @Override
+    public void testStarted() {
+        sharedCounter.reset();
+    }
+
+    @Override
+    public void testStarted(String host) {
+        testStarted();
+    }
+
+    @Override
+    public void testEnded() {
+        // NOOP
+    }
+
+    @Override
+    public void testEnded(String host) {
+        // NOOP
     }
 }
Index: src/components/org/apache/jmeter/control/gui/InterleaveControlGui.java
===================================================================
--- src/components/org/apache/jmeter/control/gui/InterleaveControlGui.java	(revision 1761202)
+++ src/components/org/apache/jmeter/control/gui/InterleaveControlGui.java	(working copy)
@@ -30,6 +30,8 @@
     private static final long serialVersionUID = 240L;
 
     private JCheckBox style;
+    
+    private JCheckBox accrossThreads;
 
     public InterleaveControlGui() {
         init();
@@ -38,11 +40,13 @@
     @Override
     public void configure(TestElement el) {
         super.configure(el);
-        if (((InterleaveControl) el).getStyle() == InterleaveControl.IGNORE_SUB_CONTROLLERS) {
+        InterleaveControl controller = (InterleaveControl) el;
+        if (controller.getStyle() == InterleaveControl.IGNORE_SUB_CONTROLLERS) {
             style.setSelected(true);
         } else {
             style.setSelected(false);
         }
+        accrossThreads.setSelected(controller.getInterleaveAccrossThreads());
     }
 
     @Override
@@ -65,6 +69,8 @@
         } else {
             ((InterleaveControl) ic).setStyle(InterleaveControl.USE_SUB_CONTROLLERS);
         }
+        
+        ((InterleaveControl) ic).setInterleaveAccrossThreads(accrossThreads.isSelected());
     }
 
     /**
@@ -74,6 +80,7 @@
     public void clearGui() {
         super.clearGui();
         style.setSelected(false);
+        accrossThreads.setSelected(false);
     }
 
     @Override
@@ -89,5 +96,8 @@
 
         style = new JCheckBox(JMeterUtils.getResString("ignore_subcontrollers")); // $NON-NLS-1$
         add(CheckBoxPanel.wrap(style));
+        
+        accrossThreads = new JCheckBox(JMeterUtils.getResString("interleave_accross_threads")); // $NON-NLS-1$
+        add(CheckBoxPanel.wrap(accrossThreads));
     }
 }