diff --git a/tools/model_generator/modelviewer.jar b/tools/model_generator/modelviewer.jar
new file mode 100644
index 00000000..27a0c016
Binary files /dev/null and b/tools/model_generator/modelviewer.jar differ
diff --git a/tools/model_generator/src/com/libiec61850/scl/model/DataAttribute.java b/tools/model_generator/src/com/libiec61850/scl/model/DataAttribute.java
index 44193d78..8362d86e 100644
--- a/tools/model_generator/src/com/libiec61850/scl/model/DataAttribute.java
+++ b/tools/model_generator/src/com/libiec61850/scl/model/DataAttribute.java
@@ -87,6 +87,8 @@ public class DataAttribute implements DataModelNode {
 
         if (!(this.sclType instanceof EnumerationType))
             throw new SclParserException("Wrong type definition for enumerated data attribute");
+        
+        this.sclType.setUsed(true);
     }
 
     private void createConstructedAttribute(DataAttributeDefinition daDefinition, TypeDeclarations typeDeclarations)
@@ -98,6 +100,8 @@ public class DataAttribute implements DataModelNode {
 
         if (!(this.sclType instanceof DataAttributeType))
             throw new SclParserException("Wrong type definition for constructed data attribute");
+        
+        this.sclType.setUsed(true);
 
         DataAttributeType dataAttributeType = (DataAttributeType) this.sclType;
 
diff --git a/tools/model_generator/src/com/libiec61850/scl/model/DataObject.java b/tools/model_generator/src/com/libiec61850/scl/model/DataObject.java
index 818bfadd..c7fae5e0 100644
--- a/tools/model_generator/src/com/libiec61850/scl/model/DataObject.java
+++ b/tools/model_generator/src/com/libiec61850/scl/model/DataObject.java
@@ -55,6 +55,9 @@ public class DataObject implements DataModelNode {
 
         if (sclType == null)
             throw new SclParserException("type declaration missing for data object.");
+        
+        /* mark type as used */
+        sclType.setUsed(true);
 
         createDataAttributes(typeDeclarations, sclType);
 
diff --git a/tools/model_generator/src/com/libiec61850/scl/model/LogicalNode.java b/tools/model_generator/src/com/libiec61850/scl/model/LogicalNode.java
index 6033732f..021dfc80 100644
--- a/tools/model_generator/src/com/libiec61850/scl/model/LogicalNode.java
+++ b/tools/model_generator/src/com/libiec61850/scl/model/LogicalNode.java
@@ -82,6 +82,9 @@ public class LogicalNode implements DataModelNode {
             dataObjects = new LinkedList<DataObject>();
 
             LogicalNodeType type = (LogicalNodeType) sclType;
+            
+            /* mark type as used */
+            type.setUsed(true);
 
             List<DataObjectDefinition> doDefinitions = type.getDataObjectDefinitions();
 
diff --git a/tools/model_generator/src/com/libiec61850/scl/types/SclType.java b/tools/model_generator/src/com/libiec61850/scl/types/SclType.java
index f6edac4a..fab834bb 100644
--- a/tools/model_generator/src/com/libiec61850/scl/types/SclType.java
+++ b/tools/model_generator/src/com/libiec61850/scl/types/SclType.java
@@ -30,6 +30,7 @@ public abstract class SclType {
 	
 	private String id = null;
 	private String description;
+	private boolean isUsed = false;
 	
 	public SclType(Node xmlNode) throws SclParserException {
 		this.id = ParserUtils.parseAttribute(xmlNode, "id");
@@ -51,4 +52,12 @@ public abstract class SclType {
 	public String getDesc() {
 		return description;
 	}
+	
+	public void setUsed(boolean isUsed) {
+	    this.isUsed = isUsed;
+	}
+	
+	public boolean isUsed() {
+	    return this.isUsed;
+	}
 }
diff --git a/tools/model_generator/src/com/libiec61850/tools/ModelViewer.java b/tools/model_generator/src/com/libiec61850/tools/ModelViewer.java
index d364959f..b1059043 100644
--- a/tools/model_generator/src/com/libiec61850/tools/ModelViewer.java
+++ b/tools/model_generator/src/com/libiec61850/tools/ModelViewer.java
@@ -26,7 +26,7 @@ import com.libiec61850.scl.types.TypeDeclarations;
 
 public class ModelViewer {
     
-    private static void showTypes(InputStream stream, String icdFile, PrintStream output, String iedName, String accessPointName) 
+    private static void showTypes(InputStream stream, String icdFile, PrintStream output, String iedName, String accessPointName, boolean unusedOnly) 
             throws SclParserException {
 
         SclParser sclParser = new SclParser(stream, false);
@@ -34,6 +34,12 @@ public class ModelViewer {
         TypeDeclarations typeDecl = sclParser.getTypeDeclarations();
 
         for (SclType type : typeDecl.getTypeDeclarations()) {
+            
+            if (unusedOnly) {
+                if (type.isUsed() == true)
+                    continue;
+            }
+            
             output.print(type.getId());
             
             if (type.getClass() == LogicalNodeType.class)
@@ -45,6 +51,10 @@ public class ModelViewer {
             else if (type.getClass() == EnumerationType.class)
                 output.print(" : Enumeration");
             
+            if (!unusedOnly)
+                if (type.isUsed() == false)
+                    System.out.print("  UNUSED TYPE!");
+            
             output.println();
         }
     }
@@ -175,6 +185,7 @@ public class ModelViewer {
             System.out.println("  -ied select IED");
             System.out.println("  -ap select AP");
             System.out.println("  -t print type list");
+            System.out.println("  -u print list of unused types");
             System.out.println("  -s print IED device model structure");
             System.out.println("  -a print list of data attributes (object references)");
             System.exit(1);
@@ -188,6 +199,7 @@ public class ModelViewer {
         String iedName = null;
         
         boolean printTypeList = false;
+        boolean printUnusedTypes = false;
         boolean printModelStructure = false;
         boolean printDataAttribtues = false;
         
@@ -225,6 +237,12 @@ public class ModelViewer {
                     
                     i++;
                     
+                }
+                else if (args[i].equals("-u")) {
+                    printUnusedTypes = true;
+                    
+                    i++;
+                    
                 }
                 else {
                      outputStream = new PrintStream(new FileOutputStream(new File(args[i])));
@@ -237,7 +255,10 @@ public class ModelViewer {
 
         try {
             if (printTypeList)
-                showTypes(stream, icdFile, outputStream, iedName, accessPointName);
+                showTypes(stream, icdFile, outputStream, iedName, accessPointName, false);
+            
+            if (printUnusedTypes)
+                showTypes(stream, icdFile, outputStream, iedName, accessPointName, true);
             
             if (printModelStructure)
                 printModelStructure(stream, icdFile, outputStream, iedName, accessPointName);