diff --git a/src/com/google/gwtorm/client/RowVersion.java b/src/com/google/gwtorm/client/RowVersion.java
new file mode 100644
index 0000000..3cae45c
--- /dev/null
+++ b/src/com/google/gwtorm/client/RowVersion.java
@@ -0,0 +1,36 @@
+// Copyright 2008 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gwtorm.client;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Annotation marking a field as the row version used for optimistic locking.
+ * <p>
+ * Fields marked with <code>RowVersion</code> must also be marked with
+ * {@link Column} and must be of type <code>int</code>. The field will be
+ * automatically incremented during INSERT and UPDATE operations, and will be
+ * tested during UPDATE and DELETE operations. Concurrent modifications of the
+ * same entity fail as the row version won't match.
+ * <p>
+ * At most one RowVersion annotation should appear in any entity.
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.FIELD)
+public @interface RowVersion {
+}
diff --git a/src/com/google/gwtorm/jdbc/gen/AccessGen.java b/src/com/google/gwtorm/jdbc/gen/AccessGen.java
index 3a1e8b2..2fd4c60 100644
--- a/src/com/google/gwtorm/jdbc/gen/AccessGen.java
+++ b/src/com/google/gwtorm/jdbc/gen/AccessGen.java
@@ -36,6 +36,7 @@
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
 
@@ -270,8 +271,22 @@
 
     final CodeGenSupport cgs = new CodeGenSupport(mv);
     cgs.setEntityType(entityType);
+
+    for (final ColumnModel col : model.getRowVersionColumns()) {
+      cgs.setFieldReference(col);
+      cgs.fieldSetBegin();
+      cgs.pushFieldValue();
+      mv.visitInsn(ICONST_1);
+      mv.visitInsn(IADD);
+      cgs.fieldSetEnd();
+    }
+    cgs.resetColumnIndex(0);
+
     if (type != DmlType.DELETE) {
-      for (final ColumnModel field : model.getDependentFields()) {
+      final List<ColumnModel> cols = new ArrayList<ColumnModel>();
+      cols.addAll(model.getDependentFields());
+      cols.addAll(model.getRowVersionFields());
+      for (final ColumnModel field : cols) {
         if (field.isNested() && field.getColumnAnnotation().notNull()) {
           for (final ColumnModel c : field.getAllLeafColumns()) {
             cgs.setFieldReference(c);
@@ -311,6 +326,17 @@
       cgs.setFieldReference(col);
       dialect.getSqlTypeInfo(col).generatePreparedStatementSet(cgs);
     }
+    if (type != DmlType.INSERT) {
+      for (final ColumnModel col : model.getRowVersionColumns()) {
+        cgs.setFieldReference(col);
+        cgs.pushSqlHandle();
+        cgs.pushColumnIndex();
+        cgs.pushFieldValue();
+        mv.visitInsn(ICONST_1);
+        mv.visitInsn(ISUB);
+        cgs.invokePreparedStatementSet("Int");
+      }
+    }
 
     mv.visitInsn(RETURN);
     mv.visitMaxs(-1, -1);
@@ -348,7 +374,11 @@
       cgs.resetColumnIndex(oldIdx);
     }
 
-    for (final ColumnModel field : model.getDependentFields()) {
+    final List<ColumnModel> cols = new ArrayList<ColumnModel>();
+    cols.addAll(model.getDependentFields());
+    cols.addAll(model.getRowVersionFields());
+    cols.addAll(model.getPrimaryKeyColumns());
+    for (final ColumnModel field : cols) {
       if (field.isNested()) {
         int oldIdx = cgs.getColumnIndex();
         final Type vType = CodeGenSupport.toType(field);
@@ -387,10 +417,6 @@
         dialect.getSqlTypeInfo(field).generateResultSetGet(cgs);
       }
     }
-    for (final ColumnModel col : model.getPrimaryKeyColumns()) {
-      cgs.setFieldReference(col);
-      dialect.getSqlTypeInfo(col).generateResultSetGet(cgs);
-    }
 
     mv.visitInsn(RETURN);
     mv.visitMaxs(-1, -1);
diff --git a/src/com/google/gwtorm/schema/ColumnModel.java b/src/com/google/gwtorm/schema/ColumnModel.java
index 754bb8a..6a56949 100644
--- a/src/com/google/gwtorm/schema/ColumnModel.java
+++ b/src/com/google/gwtorm/schema/ColumnModel.java
@@ -27,6 +27,7 @@
   protected String columnName;
   protected Column column;
   protected Collection<ColumnModel> nestedColumns;
+  protected boolean rowVersion;
   protected boolean inPrimaryKey;
 
   protected ColumnModel() {
@@ -120,6 +121,10 @@
     return getPrimitiveType() == null;
   }
 
+  public boolean isRowVersion() {
+    return rowVersion;
+  }
+
   public Column getColumnAnnotation() {
     return column;
   }
diff --git a/src/com/google/gwtorm/schema/RelationModel.java b/src/com/google/gwtorm/schema/RelationModel.java
index a8e8018..1d8a004 100644
--- a/src/com/google/gwtorm/schema/RelationModel.java
+++ b/src/com/google/gwtorm/schema/RelationModel.java
@@ -25,6 +25,7 @@
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
+import java.util.List;
 
 public abstract class RelationModel {
   protected String methodName;
@@ -125,7 +126,7 @@
   public Collection<ColumnModel> getDependentFields() {
     final ArrayList<ColumnModel> r = new ArrayList<ColumnModel>();
     for (final ColumnModel c : fieldsByFieldName.values()) {
-      if (primaryKey == null || primaryKey.getField() != c) {
+      if (!c.rowVersion && (primaryKey == null || primaryKey.getField() != c)) {
         r.add(c);
       }
     }
@@ -135,7 +136,27 @@
   public Collection<ColumnModel> getDependentColumns() {
     final ArrayList<ColumnModel> r = new ArrayList<ColumnModel>();
     for (final ColumnModel c : columnsByColumnName.values()) {
-      if (!c.inPrimaryKey) {
+      if (!c.inPrimaryKey && !c.rowVersion) {
+        r.add(c);
+      }
+    }
+    return r;
+  }
+
+  public Collection<ColumnModel> getRowVersionFields() {
+    final ArrayList<ColumnModel> r = new ArrayList<ColumnModel>();
+    for (final ColumnModel c : fieldsByFieldName.values()) {
+      if (c.rowVersion) {
+        r.add(c);
+      }
+    }
+    return r;
+  }
+
+  public Collection<ColumnModel> getRowVersionColumns() {
+    final ArrayList<ColumnModel> r = new ArrayList<ColumnModel>();
+    for (final ColumnModel c : columnsByColumnName.values()) {
+      if (c.rowVersion) {
         r.add(c);
       }
     }
@@ -164,6 +185,7 @@
   public Collection<ColumnModel> getColumns() {
     final ArrayList<ColumnModel> r = new ArrayList<ColumnModel>();
     r.addAll(getDependentColumns());
+    r.addAll(getRowVersionColumns());
     r.addAll(getPrimaryKeyColumns());
     return r;
   }
@@ -272,9 +294,13 @@
     r.append("UPDATE ");
     r.append(relationName);
     r.append(" SET ");
+    List<ColumnModel> cols;
     int nth = 1;
-    for (final Iterator<ColumnModel> i = getDependentColumns().iterator(); i
-        .hasNext();) {
+
+    cols = new ArrayList<ColumnModel>();
+    cols.addAll(getDependentColumns());
+    cols.addAll(getRowVersionColumns());
+    for (final Iterator<ColumnModel> i = cols.iterator(); i.hasNext();) {
       final ColumnModel col = i.next();
       r.append(col.getColumnName());
       r.append("=");
@@ -283,9 +309,12 @@
         r.append(",");
       }
     }
+
     r.append(" WHERE ");
-    for (final Iterator<ColumnModel> i = getPrimaryKeyColumns().iterator(); i
-        .hasNext();) {
+    cols = new ArrayList<ColumnModel>();
+    cols.addAll(getPrimaryKeyColumns());
+    cols.addAll(getRowVersionColumns());
+    for (final Iterator<ColumnModel> i = cols.iterator(); i.hasNext();) {
       final ColumnModel col = i.next();
       r.append(col.getColumnName());
       r.append("=");
@@ -303,8 +332,10 @@
     r.append(relationName);
     int nth = 1;
     r.append(" WHERE ");
-    for (final Iterator<ColumnModel> i = getPrimaryKeyColumns().iterator(); i
-        .hasNext();) {
+    final List<ColumnModel> cols = new ArrayList<ColumnModel>();
+    cols.addAll(getPrimaryKeyColumns());
+    cols.addAll(getRowVersionColumns());
+    for (final Iterator<ColumnModel> i = cols.iterator(); i.hasNext();) {
       final ColumnModel col = i.next();
       r.append(col.getColumnName());
       r.append("=");
diff --git a/src/com/google/gwtorm/schema/gwt/GwtColumnModel.java b/src/com/google/gwtorm/schema/gwt/GwtColumnModel.java
index c4ecc8e..e2c2605 100644
--- a/src/com/google/gwtorm/schema/gwt/GwtColumnModel.java
+++ b/src/com/google/gwtorm/schema/gwt/GwtColumnModel.java
@@ -20,6 +20,7 @@
 import com.google.gwt.core.ext.typeinfo.JType;
 import com.google.gwtorm.client.Column;
 import com.google.gwtorm.client.OrmException;
+import com.google.gwtorm.client.RowVersion;
 import com.google.gwtorm.schema.ColumnModel;
 
 import java.util.ArrayList;
@@ -96,6 +97,12 @@
     }
 
     primitiveType = toClass(field.getType());
+    rowVersion = field.getAnnotation(RowVersion.class) != null;
+    if (rowVersion && primitiveType != Integer.TYPE) {
+      throw new OrmException("Field " + field.getName() + " of "
+          + field.getEnclosingType().getQualifiedSourceName()
+          + " must have type 'int'");
+    }
 
     if (isNested()) {
       final List<GwtColumnModel> col = new ArrayList<GwtColumnModel>();
diff --git a/src/com/google/gwtorm/schema/java/JavaColumnModel.java b/src/com/google/gwtorm/schema/java/JavaColumnModel.java
index 47c79f5..082a6a2 100644
--- a/src/com/google/gwtorm/schema/java/JavaColumnModel.java
+++ b/src/com/google/gwtorm/schema/java/JavaColumnModel.java
@@ -16,6 +16,7 @@
 
 import com.google.gwtorm.client.Column;
 import com.google.gwtorm.client.OrmException;
+import com.google.gwtorm.client.RowVersion;
 import com.google.gwtorm.schema.ColumnModel;
 import com.google.gwtorm.schema.Util;
 
@@ -41,6 +42,12 @@
           + field.getDeclaringClass().getName() + " must not be final");
     }
 
+    rowVersion = field.getAnnotation(RowVersion.class) != null;
+    if (rowVersion && field.getType() != Integer.TYPE) {
+      throw new OrmException("Field " + field.getName() + " of "
+          + field.getDeclaringClass().getName() + " must have type 'int'");
+    }
+
     if (isNested()) {
       final List<JavaColumnModel> col = new ArrayList<JavaColumnModel>();
       Class<?> in = field.getType();