diff --git a/jOOQ/src/main/java/org/jooq/AggregateFunction.java b/jOOQ/src/main/java/org/jooq/AggregateFunction.java
new file mode 100644
index 0000000000..ddc9a90565
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/AggregateFunction.java
@@ -0,0 +1,47 @@
+/**
+ * Copyright (c) 2009-2011, Lukas Eder, lukas.eder@gmail.com
+ * All rights reserved.
+ *
+ * This software is licensed to you under the Apache License, Version 2.0
+ * (the "License"); You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * . Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * . Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * . Neither the name "jOOQ" nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.jooq;
+
+/**
+ * An aggregate function is a special field that is usually used in a
+ * <code>GROUP BY</code> context. It is also the base for window function
+ * construction.
+ *
+ * @author Lukas Eder
+ */
+public interface AggregateFunction<T> extends Field<T> {
+
+}
diff --git a/jOOQ/src/main/java/org/jooq/impl/AggregateFunctionImpl.java b/jOOQ/src/main/java/org/jooq/impl/AggregateFunctionImpl.java
new file mode 100644
index 0000000000..ffa313e1d4
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/impl/AggregateFunctionImpl.java
@@ -0,0 +1,56 @@
+/**
+ * Copyright (c) 2009-2011, Lukas Eder, lukas.eder@gmail.com
+ * All rights reserved.
+ *
+ * This software is licensed to you under the Apache License, Version 2.0
+ * (the "License"); You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * . Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * . Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * . Neither the name "jOOQ" nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.jooq.impl;
+
+import org.jooq.AggregateFunction;
+import org.jooq.DataType;
+import org.jooq.QueryPart;
+
+class AggregateFunctionImpl<T> extends Function<T> implements AggregateFunction<T> {
+
+    /**
+     * Generated UID
+     */
+    private static final long serialVersionUID = 1952351506930280715L;
+
+    AggregateFunctionImpl(String name, DataType<T> type, QueryPart... arguments) {
+        super(name, type, arguments);
+    }
+
+    AggregateFunctionImpl(Term term, DataType<T> type, QueryPart... arguments) {
+        super(term, type, arguments);
+    }
+}
diff --git a/jOOQ/src/main/java/org/jooq/impl/Count.java b/jOOQ/src/main/java/org/jooq/impl/Count.java
index 402949df66..dad022db4c 100644
--- a/jOOQ/src/main/java/org/jooq/impl/Count.java
+++ b/jOOQ/src/main/java/org/jooq/impl/Count.java
@@ -43,7 +43,7 @@ import org.jooq.RenderContext;
 /**
  * @author Lukas Eder
  */
-class Count extends Function<Integer> {
+class Count extends AggregateFunctionImpl<Integer> {
 
     private static final long serialVersionUID = 4685583105296376461L;
 
diff --git a/jOOQ/src/main/java/org/jooq/impl/Factory.java b/jOOQ/src/main/java/org/jooq/impl/Factory.java
index 2a94f31f74..4eef4a77ff 100644
--- a/jOOQ/src/main/java/org/jooq/impl/Factory.java
+++ b/jOOQ/src/main/java/org/jooq/impl/Factory.java
@@ -54,6 +54,7 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 
+import org.jooq.AggregateFunction;
 import org.jooq.ArrayRecord;
 import org.jooq.Attachable;
 import org.jooq.Batch;
@@ -2107,50 +2108,50 @@ public class Factory implements FactoryOperations {
     /**
      * Get the count(*) function
      */
-    public static Field<Integer> count() {
+    public static AggregateFunction<Integer> count() {
         return new Count(field("*", Integer.class), false);
     }
 
     /**
      * Get the count(field) function
      */
-    public static Field<Integer> count(Field<?> field) {
+    public static AggregateFunction<Integer> count(Field<?> field) {
         return new Count(field, false);
     }
 
     /**
      * Get the count(distinct field) function
      */
-    public static Field<Integer> countDistinct(Field<?> field) {
+    public static AggregateFunction<Integer> countDistinct(Field<?> field) {
         return new Count(field, true);
     }
 
     /**
      * Get the max value over a field: max(field)
      */
-    public static <T> Field<T> max(Field<T> field) {
-        return function("max", field.getDataType(), field);
+    public static <T> AggregateFunction<T> max(Field<T> field) {
+        return new AggregateFunctionImpl<T>("max", field.getDataType(), field);
     }
 
     /**
      * Get the min value over a field: min(field)
      */
-    public static <T> Field<T> min(Field<T> field) {
-        return function("min", field.getDataType(), field);
+    public static <T> AggregateFunction<T> min(Field<T> field) {
+        return new AggregateFunctionImpl<T>("min", field.getDataType(), field);
     }
 
     /**
      * Get the sum over a numeric field: sum(field)
      */
-    public static Field<BigDecimal> sum(Field<? extends Number> field) {
-        return function("sum", SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> sum(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>("sum", SQLDataType.NUMERIC, field);
     }
 
     /**
      * Get the average over a numeric field: avg(field)
      */
-    public static Field<BigDecimal> avg(Field<? extends Number> field) {
-        return function("avg", SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> avg(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>("avg", SQLDataType.NUMERIC, field);
     }
 
     /**
@@ -2163,8 +2164,8 @@ public class Factory implements FactoryOperations {
      * <li>Sybase SQL Anywhere</li>
      * </ul>
      */
-    public static Field<BigDecimal> median(Field<? extends Number> field) {
-        return function("median", SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> median(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>("median", SQLDataType.NUMERIC, field);
     }
 
     /**
@@ -2184,8 +2185,8 @@ public class Factory implements FactoryOperations {
      * <li>Sybase SQL Anywhere</li>
      * </ul>
      */
-    public static Field<BigDecimal> stddevPop(Field<? extends Number> field) {
-        return new Function<BigDecimal>(Term.STDDEV_POP, SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> stddevPop(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>(Term.STDDEV_POP, SQLDataType.NUMERIC, field);
     }
 
     /**
@@ -2205,8 +2206,8 @@ public class Factory implements FactoryOperations {
      * <li>Sybase SQL Anywhere</li>
      * </ul>
      */
-    public static Field<BigDecimal> stddevSamp(Field<? extends Number> field) {
-        return new Function<BigDecimal>(Term.STDDEV_SAMP, SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> stddevSamp(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>(Term.STDDEV_SAMP, SQLDataType.NUMERIC, field);
     }
 
     /**
@@ -2226,8 +2227,8 @@ public class Factory implements FactoryOperations {
      * <li>Sybase SQL Anywhere</li>
      * </ul>
      */
-    public static Field<BigDecimal> varPop(Field<? extends Number> field) {
-        return new Function<BigDecimal>(Term.VAR_POP, SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> varPop(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>(Term.VAR_POP, SQLDataType.NUMERIC, field);
     }
 
     /**
@@ -2245,8 +2246,8 @@ public class Factory implements FactoryOperations {
      * <li>Sybase SQL Anywhere</li>
      * </ul>
      */
-    public static Field<BigDecimal> varSamp(Field<? extends Number> field) {
-        return new Function<BigDecimal>(Term.VAR_SAMP, SQLDataType.NUMERIC, field);
+    public static AggregateFunction<BigDecimal> varSamp(Field<? extends Number> field) {
+        return new AggregateFunctionImpl<BigDecimal>(Term.VAR_SAMP, SQLDataType.NUMERIC, field);
     }
 
     // -------------------------------------------------------------------------