diff --git a/prism/src/explicit/MDP.java b/prism/src/explicit/MDP.java
index 400636fa..6f47adb9 100644
--- a/prism/src/explicit/MDP.java
+++ b/prism/src/explicit/MDP.java
@@ -44,6 +44,9 @@ public class MDP extends Model
 	// Transition function (Steps)
 	protected List<List<Distribution>> trans;
 
+	// Action labels
+	protected List<List<Object>> actions;
+	
 	// Rewards
 	protected List<List<Double>> transRewards;
 	protected Double transRewardsConstant;
@@ -85,6 +88,7 @@ public class MDP extends Model
 		for (int i = 0; i < numStates; i++) {
 			trans.add(new ArrayList<Distribution>());
 		}
+		actions = null;
 		clearAllRewards();
 	}
 
@@ -104,6 +108,8 @@ public class MDP extends Model
 		}
 		maxNumDistrsOk = false;
 		trans.get(s).clear();
+		if (actions != null && actions.get(s) != null)
+			actions.get(s).clear();
 		if (transRewards != null && transRewards.get(s) != null)
 			transRewards.get(s).clear();
 	}
@@ -124,6 +130,8 @@ public class MDP extends Model
 	{
 		for (int i = 0; i < numToAdd; i++) {
 			trans.add(new ArrayList<Distribution>());
+			if (actions != null)
+				actions.add(null);
 			if (transRewards != null)
 				transRewards.add(null);
 			numStates++;
@@ -151,6 +159,9 @@ public class MDP extends Model
 				return i;
 		}
 		set.add(distr);
+		// Add null action if necessary
+		if (actions != null && actions.get(s) != null)
+			actions.get(s).add(null);
 		// Add zero reward if necessary
 		if (transRewards != null && transRewards.get(s) != null)
 			transRewards.get(s).add(0.0);
@@ -170,6 +181,30 @@ public class MDP extends Model
 		transRewardsConstant = null;
 	}
 
+	/**
+	 * Set the action label for choice i in some state s.
+	 */
+	public void setAction(int s, int i, Object o)
+	{
+		// If no actions array created yet, create it
+		if (actions == null) {
+			actions = new ArrayList<List<Object>>(numStates);
+			for (int j = 0; j < numStates; j++)
+				actions.add(null);
+		}
+		// If no actions for state i yet, create list
+		if (actions.get(s) == null) {
+			int n = trans.get(s).size();
+			List<Object> list = new ArrayList<Object>(n);
+			for (int j = 0; j < n; j++) {
+				list.add(0.0);
+			}
+			actions.set(s, list);
+		}
+		// Set actions
+		actions.get(s).set(i, o);
+	}
+
 	/**
 	 * Set a constant reward for all transitions
 	 */
@@ -231,6 +266,17 @@ public class MDP extends Model
 		return trans.get(s).get(i);
 	}
 	
+	/**
+	 * Get the action (if any) for choice i of state s.
+	 */
+	public Object getAction(int s, int i)
+	{
+		List<Object> list;
+		if (actions == null || (list = actions.get(s)) == null)
+			return null;
+		return list.get(i);
+	}
+
 	/**
 	 * Get the transition reward (if any) for choice i of state s.
 	 */
@@ -615,9 +661,10 @@ public class MDP extends Model
 				j = -1;
 				for (Distribution distr : trans.get(i)) {
 					j++;
+					out.write(i + " -> " + i + "." + j + " [ arrowhead=none,label=\"" + j + "\" ];\n");
+					out.write(i + "." + j + " [ shape=circle,width=0.1,height=0.1,label=\"\" ];\n");
 					for (Map.Entry<Integer, Double> e : distr) {
-						out.write(i + " -> " + e.getKey() + " [ label=\"");
-						out.write(j + ":" + e.getValue() + "\" ];\n");
+						out.write(i + "." + j + " -> " + e.getKey() + " [ label=\"" + e.getValue() + "\" ];\n");
 					}
 				}
 			}
@@ -657,6 +704,8 @@ public class MDP extends Model
 			else
 				s += ", ";
 			s += i + ": " + trans.get(i);
+			if (actions != null)
+				s += actions.get(i);
 			if (transRewards != null)
 				s += transRewards.get(i);
 		}
@@ -678,6 +727,7 @@ public class MDP extends Model
 			return false;
 		if (!trans.equals(mdp.trans))
 			return false;
+		// TODO: compare actions (complicated: null = null,null,null,...)
 		// TODO: compare rewards (complicated: null = 0,0,0,0)
 		return true;
 	}