diff --git a/src/main/java/li/strolch/agent/api/ElementMap.java b/src/main/java/li/strolch/agent/api/ElementMap.java
index 3d89779f6..b6d2f9a6b 100644
--- a/src/main/java/li/strolch/agent/api/ElementMap.java
+++ b/src/main/java/li/strolch/agent/api/ElementMap.java
@@ -97,4 +97,8 @@ public interface ElementMap<T extends StrolchElement> {
 	public void remove(StrolchTransaction tx, T element);
 
 	public void removeAll(StrolchTransaction tx, List<T> elements);
+	
+	public long removeAll(StrolchTransaction tx);
+	
+	public long removeAllBy(StrolchTransaction tx, String type);
 }
diff --git a/src/main/java/li/strolch/agent/impl/CachedElementMap.java b/src/main/java/li/strolch/agent/impl/CachedElementMap.java
index de7b43ec2..7671c0a4a 100644
--- a/src/main/java/li/strolch/agent/impl/CachedElementMap.java
+++ b/src/main/java/li/strolch/agent/impl/CachedElementMap.java
@@ -24,6 +24,9 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import li.strolch.agent.api.ElementMap;
 import li.strolch.model.StrolchElement;
 import li.strolch.persistence.api.StrolchDao;
@@ -37,6 +40,7 @@ import ch.eitchnet.utils.dbc.DBC;
  */
 public abstract class CachedElementMap<T extends StrolchElement> implements ElementMap<T> {
 
+	private static final Logger logger = LoggerFactory.getLogger(CachedElementMap.class);
 	private Set<String> allKeys;
 	private Map<String, Map<String, T>> elementMap;
 
@@ -374,4 +378,61 @@ public abstract class CachedElementMap<T extends StrolchElement> implements Elem
 		// last is to perform DB changes
 		getDao(tx).removeAll(elements);
 	}
+
+	@Override
+	public long removeAll(StrolchTransaction tx) {
+
+		if (this.elementMap.isEmpty())
+			return 0;
+
+		long removed = 0;
+
+		synchronized (this.elementMap) {
+			Set<String> types = this.elementMap.keySet();
+			for (String type : types) {
+
+				Map<String, T> byType = this.elementMap.get(type);
+				removed += byType.size();
+				byType.clear();
+			}
+		}
+
+		// last is to perform DB changes
+		long daoRemoved = getDao(tx).removeAll();
+
+		if (removed != daoRemoved) {
+			String msg = "Removed {0} elements from cached map, but dao removed {1} elements!";
+			logger.error(MessageFormat.format(msg, removed, daoRemoved));
+		}
+
+		return removed;
+	}
+
+	@Override
+	public long removeAllBy(StrolchTransaction tx, String type) {
+
+		long removed = 0;
+		String msg = "The elements with type {0} can not be removed as they do not exist!"; //$NON-NLS-1$
+
+		synchronized (this.elementMap) {
+			Map<String, T> byType = this.elementMap.get(type);
+			if (byType == null) {
+				msg = MessageFormat.format(msg, type);
+				throw new StrolchPersistenceException(msg);
+			}
+
+			removed = byType.size();
+			byType.clear();
+		}
+
+		// last is to perform DB changes
+		long daoRemoved = getDao(tx).removeAllBy(type);
+
+		if (removed != daoRemoved) {
+			msg = "Removed {0} elements from cached map for type {1}, but dao removed {3} elements!";
+			logger.error(MessageFormat.format(msg, removed, type, daoRemoved));
+		}
+
+		return removed;
+	}
 }
diff --git a/src/main/java/li/strolch/agent/impl/TransactionalElementMap.java b/src/main/java/li/strolch/agent/impl/TransactionalElementMap.java
index 745fffd07..e1c0fce66 100644
--- a/src/main/java/li/strolch/agent/impl/TransactionalElementMap.java
+++ b/src/main/java/li/strolch/agent/impl/TransactionalElementMap.java
@@ -95,14 +95,24 @@ public abstract class TransactionalElementMap<T extends StrolchElement> implemen
 		getDao(tx).saveAll(elements);
 	}
 
+	@Override
+	public List<T> updateAll(StrolchTransaction tx, List<T> elements) {
+		getDao(tx).updateAll(elements);
+		return elements;
+	}
+
 	@Override
 	public void removeAll(StrolchTransaction tx, List<T> elements) {
 		getDao(tx).removeAll(elements);
 	}
 
 	@Override
-	public List<T> updateAll(StrolchTransaction tx, List<T> elements) {
-		getDao(tx).updateAll(elements);
-		return elements;
+	public long removeAll(StrolchTransaction tx) {
+		return getDao(tx).removeAll();
+	}
+
+	@Override
+	public long removeAllBy(StrolchTransaction tx, String type) {
+		return getDao(tx).removeAllBy(type);
 	}
 }
diff --git a/src/main/java/li/strolch/agent/impl/TransientRealm.java b/src/main/java/li/strolch/agent/impl/TransientRealm.java
index 639c93de5..c8a04fdd3 100644
--- a/src/main/java/li/strolch/agent/impl/TransientRealm.java
+++ b/src/main/java/li/strolch/agent/impl/TransientRealm.java
@@ -24,8 +24,8 @@ import li.strolch.agent.api.ComponentContainer;
 import li.strolch.agent.api.OrderMap;
 import li.strolch.agent.api.ResourceMap;
 import li.strolch.agent.api.StrolchRealm;
+import li.strolch.model.ModelStatistics;
 import li.strolch.model.xml.XmlModelSaxFileReader;
-import li.strolch.model.xml.XmlModelSaxReader.XmlModelStatistics;
 import li.strolch.persistence.api.PersistenceHandler;
 import li.strolch.persistence.api.StrolchTransaction;
 import li.strolch.persistence.inmemory.InMemoryPersistence;
@@ -95,7 +95,7 @@ public class TransientRealm extends StrolchRealm {
 	@Override
 	public void start() {
 
-		XmlModelStatistics statistics;
+		ModelStatistics statistics;
 		try (StrolchTransaction tx = openTx()) {
 			InMemoryElementListener elementListener = new InMemoryElementListener(tx);
 			XmlModelSaxFileReader handler = new XmlModelSaxFileReader(elementListener, modelFile);
diff --git a/src/main/java/li/strolch/persistence/api/StrolchDao.java b/src/main/java/li/strolch/persistence/api/StrolchDao.java
index 880759d96..cefb8e458 100644
--- a/src/main/java/li/strolch/persistence/api/StrolchDao.java
+++ b/src/main/java/li/strolch/persistence/api/StrolchDao.java
@@ -54,4 +54,8 @@ public interface StrolchDao<T extends StrolchElement> {
 	public void remove(T element);
 
 	public void removeAll(List<T> elements);
+	
+	public long removeAll();
+	
+	public long removeAllBy(String type);
 }
diff --git a/src/main/java/li/strolch/persistence/inmemory/InMemoryDao.java b/src/main/java/li/strolch/persistence/inmemory/InMemoryDao.java
index 259232dab..e8732e8f3 100644
--- a/src/main/java/li/strolch/persistence/inmemory/InMemoryDao.java
+++ b/src/main/java/li/strolch/persistence/inmemory/InMemoryDao.java
@@ -142,6 +142,10 @@ public class InMemoryDao<T extends StrolchElement> implements StrolchDao<T> {
 		Map<String, T> byType = this.elementMap.get(element.getType());
 		if (byType != null) {
 			byType.remove(element.getId());
+
+			if (byType.isEmpty()) {
+				this.elementMap.remove(element.getType());
+			}
 		}
 	}
 
@@ -151,4 +155,27 @@ public class InMemoryDao<T extends StrolchElement> implements StrolchDao<T> {
 			remove(element);
 		}
 	}
+
+	@Override
+	public long removeAll() {
+		long removed = 0;
+
+		for (String type : this.elementMap.keySet()) {
+			Map<String, T> byType = this.elementMap.remove(type);
+			removed += byType.size();
+			byType.clear();
+		}
+
+		return removed;
+	}
+
+	@Override
+	public long removeAllBy(String type) {
+		Map<String, T> byType = this.elementMap.remove(type);
+		if (byType == null)
+			return 0;
+		long removed = byType.size();
+		byType.clear();
+		return removed;
+	}
 }