diff --git a/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmEngine.java b/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmEngine.java
index 52ac74f..3a6994c 100644
--- a/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmEngine.java
+++ b/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmEngine.java
@@ -4,7 +4,7 @@ import android.util.Log;
 
 import com.qualcomm.robotcore.eventloop.opmode.OpMode;
 
-import java.util.ArrayList;
+import java.util.concurrent.CopyOnWriteArrayList;
 
 /**
  * CyberarmEngine Version 2.0 | October 26th 2018
@@ -15,11 +15,12 @@ public abstract class CyberarmEngine extends OpMode {
 
   public static CyberarmEngine instance;
   //Array To Hold States
-  private ArrayList<CyberarmState> cyberarmStates = new ArrayList<>();
+  private CopyOnWriteArrayList<CyberarmState> cyberarmStates = new CopyOnWriteArrayList<>();
   private int activeStateIndex = 0;
   private boolean isRunning;
 
-  private static String TAG = "PROGRAM.ENGINE: ";
+  private static String TAG = "PROGRAM.ENGINE";
+  public boolean showStateChildrenListInTelemetry = false;
 
   /**
    * Called when INIT button on Driver Station is pushed
@@ -83,6 +84,11 @@ public abstract class CyberarmEngine extends OpMode {
 
       // Add telemetry to show currently running state
     telemetry.addLine("Running state: " +state.getClass().getSimpleName() + ". State: " + activeStateIndex + " of " + (cyberarmStates.size()-1));
+    if (showStateChildrenListInTelemetry && state.hasChildren()) {
+      for(CyberarmState child: state.children) {
+        telemetry.addLine("    Child: " + child.getClass().getSimpleName() + " [" + child.children.size() + "] grandchildren");
+      }
+    }
     telemetry.addLine();
 
     if (state.getHasFinished() && state.childrenHaveFinished()) {
diff --git a/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmState.java b/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmState.java
index bb8c8e9..1a91428 100644
--- a/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmState.java
+++ b/TeamCode/src/main/java/org/cyberarm/engine/V2/CyberarmState.java
@@ -2,7 +2,7 @@ package org.cyberarm.engine.V2;
 
 import android.util.Log;
 
-import java.util.ArrayList;
+import java.util.concurrent.CopyOnWriteArrayList;
 
 /**
  * A State for use with CyberarmEngineV2
@@ -12,7 +12,7 @@ public abstract class CyberarmState implements Runnable {
   private volatile boolean isRunning, hasFinished;
   public static String TAG = "PROGRAM.STATE";
   public CyberarmEngine engine = CyberarmEngine.instance;
-  public ArrayList<CyberarmState> children = new ArrayList<>();
+  public CopyOnWriteArrayList<CyberarmState> children = new CopyOnWriteArrayList<>();
   public long startTime = 0;
   public int insertOffset = 1;
 
@@ -90,7 +90,7 @@ public abstract class CyberarmState implements Runnable {
 
   /**
    * Have all of the states children finished running themselves?
-   * @return Wether or not all children have finished running
+   * @return Whether or not all children have finished running
    */
   public boolean childrenHaveFinished() {
     return childrenHaveFinished(children);
@@ -98,10 +98,10 @@ public abstract class CyberarmState implements Runnable {
 
   /**
    * Have all of the states children finished running themselves?
-   * @param kids ArrayList of children to check for hasFinished()
+   * @param kids CopyOnWriteArrayList of children to check for hasFinished()
    * @return Whether or not all children have finished running
    */
-  public boolean childrenHaveFinished(ArrayList<CyberarmState> kids) {
+  public boolean childrenHaveFinished(CopyOnWriteArrayList<CyberarmState> kids) {
     boolean allDone = true;
 
       for (CyberarmState state : kids) {