diff --git a/.gitignore b/.gitignore
new file mode 100644
index 000000000..e5aa5b3c6
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.idea
+*.iml
+target
\ No newline at end of file
diff --git a/code/src/main/java/com/googlecode/cqengine/engine/CollectionQueryEngine.java b/code/src/main/java/com/googlecode/cqengine/engine/CollectionQueryEngine.java
index 3ea5d404b..b793fa883 100644
--- a/code/src/main/java/com/googlecode/cqengine/engine/CollectionQueryEngine.java
+++ b/code/src/main/java/com/googlecode/cqengine/engine/CollectionQueryEngine.java
@@ -82,6 +82,8 @@ public class CollectionQueryEngine<O> implements QueryEngineInternal<O> {
     // A key used to store the root query in the QueryOptions, so it may be accessed by partial indexes...
     public static final String ROOT_QUERY = "ROOT_QUERY";
 
+    public static final String DISABLE_DIRTY_CHECK_OPTION = "DISABLE_DIRTY_CHECK";
+
     private volatile Persistence<O, ? extends Comparable> persistence;
     private volatile ObjectStore<O> objectStore;
 
@@ -171,6 +173,10 @@ else if (index instanceof AttributeIndex) {
      * @param <A> The type of objects indexed
      */
     <A> void addAttributeIndex(AttributeIndex<A, O> attributeIndex, QueryOptions queryOptions) {
+        Object dirtyCheck = queryOptions.get(DISABLE_DIRTY_CHECK_OPTION);
+        if (dirtyCheck != null && (Boolean) dirtyCheck) {
+            attributeIndex.checkDirty();
+        }
         Attribute<O, A> attribute = attributeIndex.getAttribute();
         Set<Index<O>> indexesOnThisAttribute = attributeIndexes.get(attribute);
         if (indexesOnThisAttribute == null) {
diff --git a/code/src/main/java/com/googlecode/cqengine/index/AttributeIndex.java b/code/src/main/java/com/googlecode/cqengine/index/AttributeIndex.java
index b4c8c5d75..d6cc90e56 100644
--- a/code/src/main/java/com/googlecode/cqengine/index/AttributeIndex.java
+++ b/code/src/main/java/com/googlecode/cqengine/index/AttributeIndex.java
@@ -31,4 +31,9 @@ public interface AttributeIndex<A, O> extends Index<O> {
      * @return The attribute indexed by this index
      */
     Attribute<O, A> getAttribute();
+
+    /**
+     * Checks if this index is alredy being used by another collection.
+     */
+    void checkDirty();
 }
diff --git a/code/src/main/java/com/googlecode/cqengine/index/sqlite/SQLiteIdentityIndex.java b/code/src/main/java/com/googlecode/cqengine/index/sqlite/SQLiteIdentityIndex.java
index 4fb26e3a4..623af05af 100644
--- a/code/src/main/java/com/googlecode/cqengine/index/sqlite/SQLiteIdentityIndex.java
+++ b/code/src/main/java/com/googlecode/cqengine/index/sqlite/SQLiteIdentityIndex.java
@@ -20,10 +20,7 @@
 import com.googlecode.cqengine.attribute.SimpleAttribute;
 import com.googlecode.cqengine.index.Index;
 import com.googlecode.cqengine.index.sqlite.support.PojoSerializer;
-import com.googlecode.cqengine.index.support.CloseableIterable;
-import com.googlecode.cqengine.index.support.KeyStatistics;
-import com.googlecode.cqengine.index.support.KeyValue;
-import com.googlecode.cqengine.index.support.SortedKeyStatisticsAttributeIndex;
+import com.googlecode.cqengine.index.support.*;
 import com.googlecode.cqengine.index.support.indextype.NonHeapTypeIndex;
 import com.googlecode.cqengine.persistence.support.ObjectSet;
 import com.googlecode.cqengine.persistence.support.ObjectStore;
@@ -50,6 +47,7 @@ public class SQLiteIdentityIndex<A extends Comparable<A>, O> implements Identity
     final Class<O> objectType;
     final SimpleAttribute<O, A> primaryKeyAttribute;
     final SimpleAttribute<A, O> foreignKeyAttribute;
+    private boolean dirty = false;
 
     public SQLiteIdentityIndex(final SimpleAttribute<O, A> primaryKeyAttribute) {
         this.sqLiteIndex = new SQLiteIndex<A, O, byte[]>(
@@ -80,6 +78,14 @@ public Attribute<O, A> getAttribute() {
         return sqLiteIndex.getAttribute();
     }
 
+    @Override
+    public void checkDirty() {
+        if (dirty) {
+            throw new AbstractAttributeIndex.DirtyIndexException("Index of attribute: " + primaryKeyAttribute.getAttributeName() + " - is in use.");
+        }
+        dirty = true;
+    }
+
     @Override
     public boolean isMutable() {
         return sqLiteIndex.isMutable();
diff --git a/code/src/main/java/com/googlecode/cqengine/index/sqlite/SimplifiedSQLiteIndex.java b/code/src/main/java/com/googlecode/cqengine/index/sqlite/SimplifiedSQLiteIndex.java
index e5b7e88d5..3494a9816 100644
--- a/code/src/main/java/com/googlecode/cqengine/index/sqlite/SimplifiedSQLiteIndex.java
+++ b/code/src/main/java/com/googlecode/cqengine/index/sqlite/SimplifiedSQLiteIndex.java
@@ -44,6 +44,7 @@ public abstract class SimplifiedSQLiteIndex<A extends Comparable<A>, O, K extend
     final Attribute<O, A> attribute;
     final String tableNameSuffix;
     volatile SQLiteIndex<A, O, K> backingIndex;
+    private boolean dirty = false;
 
     protected SimplifiedSQLiteIndex(Class<? extends SQLitePersistence<O, A>> persistenceType, Attribute<O, A> attribute, String tableNameSuffix) {
         this.persistenceType = persistenceType;
@@ -248,4 +249,12 @@ public int hashCode() {
         result = 31 * result + attribute.hashCode();
         return result;
     }
+
+    @Override
+    public void checkDirty() {
+        if (dirty) {
+            throw new AbstractAttributeIndex.DirtyIndexException("Index of attribute: " + attribute.getAttributeName() + " - is in use.");
+        }
+        dirty = true;
+    }
 }
diff --git a/code/src/main/java/com/googlecode/cqengine/index/support/AbstractAttributeIndex.java b/code/src/main/java/com/googlecode/cqengine/index/support/AbstractAttributeIndex.java
index 5f7559048..09765ca67 100644
--- a/code/src/main/java/com/googlecode/cqengine/index/support/AbstractAttributeIndex.java
+++ b/code/src/main/java/com/googlecode/cqengine/index/support/AbstractAttributeIndex.java
@@ -38,6 +38,8 @@ public abstract class AbstractAttributeIndex<A, O> implements AttributeIndex<A,
 
     protected final Attribute<O, A> attribute;
 
+    private boolean dirty = false;
+
     /**
      * Protected constructor, called by subclasses.
      *
@@ -60,6 +62,19 @@ public Attribute<O, A> getAttribute() {
         return attribute;
     }
 
+    public static class DirtyIndexException extends RuntimeException {
+        public DirtyIndexException(String message) {
+            super(message);
+        }
+    }
+
+    public void checkDirty() {
+        if (dirty) {
+            throw new DirtyIndexException("Index of attribute: " + attribute.getAttributeName() + " - is in use.");
+        }
+        dirty = true;
+    }
+
     /**
      * {@inheritDoc}
      */
diff --git a/code/src/main/java/com/googlecode/cqengine/index/support/PartialIndex.java b/code/src/main/java/com/googlecode/cqengine/index/support/PartialIndex.java
index daf38ea43..da71e3147 100644
--- a/code/src/main/java/com/googlecode/cqengine/index/support/PartialIndex.java
+++ b/code/src/main/java/com/googlecode/cqengine/index/support/PartialIndex.java
@@ -90,6 +90,7 @@ public abstract class PartialIndex<A, O, I extends AttributeIndex<A, O>> impleme
     protected final Query<O> filterQuery;
     protected final Attribute<O, A> attribute;
     protected volatile I backingIndex;
+    private boolean dirty = false;
 
     /**
      * Protected constructor, called by subclasses.
@@ -113,6 +114,13 @@ protected I backingIndex() {
         return backingIndex;
     }
 
+    @Override
+    public void checkDirty() {
+        if (dirty) {
+            throw new AbstractAttributeIndex.DirtyIndexException("Index of attribute: " + attribute.getAttributeName() + " - is in use.");
+        }
+        dirty = true;
+    }
 
     public Attribute<O, A> getAttribute() {
         return backingIndex().getAttribute();