diff --git a/com.eclipsesource.tabris.test/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecoratorTest.java b/com.eclipsesource.tabris.test/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecoratorTest.java
index aed8d39..bb8f9db 100644
--- a/com.eclipsesource.tabris.test/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecoratorTest.java
+++ b/com.eclipsesource.tabris.test/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecoratorTest.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2013 EclipseSource and others.
+ * Copyright (c) 2013, 2021 EclipseSource and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -69,4 +69,32 @@ public void testSetsOverlay() {
     verify( shell ).setData( WhiteListEntry.OVERLAY_COLOR.getKey(), expectedColor );
   }
 
+  @Test( expected = IllegalArgumentException.class )
+  public void testSetTitlebarColor_FailsWithNegativeAlpha() {
+    Color color = new Color( display, 233, 244, 255 );
+
+    decorator.setTitlebarColor( color, -34 );
+  }
+
+  @Test( expected = IllegalArgumentException.class )
+  public void testSetTitlebarColor_FailsWithToBigAlpha() {
+    Color color = new Color( display, 233, 244, 255 );
+
+    decorator.setTitlebarColor( color, 256 );
+  }
+
+  @Test( expected = IllegalArgumentException.class )
+  public void testSetTitlebarColor_FailsWithNullColor() {
+    decorator.setTitlebarColor( null, 254 );
+  }
+
+  @Test
+  public void testSetTitlebarColor() {
+    Color color = new Color( display, 233, 244, 255 );
+    decorator.setTitlebarColor( color, 34 );
+
+    JsonArray expectedColor = new JsonArray().add( 233 ).add( 244 ).add( 255 ).add( 34 );
+    verify( shell ).setData( WhiteListEntry.TITLEBAR_COLOR.getKey(), expectedColor );
+  }
+
 }
diff --git a/com.eclipsesource.tabris/src/com/eclipsesource/tabris/internal/DataWhitelist.java b/com.eclipsesource.tabris/src/com/eclipsesource/tabris/internal/DataWhitelist.java
index 1f9bf84..93b70e6 100644
--- a/com.eclipsesource.tabris/src/com/eclipsesource/tabris/internal/DataWhitelist.java
+++ b/com.eclipsesource.tabris/src/com/eclipsesource/tabris/internal/DataWhitelist.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2013, 2020 EclipseSource and others.
+ * Copyright (c) 2013, 2021 EclipseSource and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -33,6 +33,7 @@ public enum WhiteListEntry {
     SHOW_TOUCH( "showTouch" ),
     BADGE_VALUE( "badgeValue" ),
     OVERLAY_COLOR( "overlayColor" ),
+    TITLEBAR_COLOR( "titlebarColor" ),
     TEXT_REPLACEMENT( "textReplacement" ),
     AUTO_CAPITALIZE( "autoCapitalize" ),
     KEYBOARD_APPEARANCE_MODE( "keyboardAppearanceMode" ),
diff --git a/com.eclipsesource.tabris/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecorator.java b/com.eclipsesource.tabris/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecorator.java
index b943af9..e9dfc0f 100644
--- a/com.eclipsesource.tabris/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecorator.java
+++ b/com.eclipsesource.tabris/src/com/eclipsesource/tabris/widgets/enhancement/ShellDecorator.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2013 EclipseSource and others.
+ * Copyright (c) 2013, 2021 EclipseSource and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -13,6 +13,7 @@
 import static com.eclipsesource.tabris.internal.Clauses.when;
 import static com.eclipsesource.tabris.internal.Clauses.whenNull;
 import static com.eclipsesource.tabris.internal.DataWhitelist.WhiteListEntry.OVERLAY_COLOR;
+import static com.eclipsesource.tabris.internal.DataWhitelist.WhiteListEntry.TITLEBAR_COLOR;
 import static com.eclipsesource.tabris.internal.WidgetsUtil.setData;
 
 import org.eclipse.rap.json.JsonArray;
@@ -51,4 +52,23 @@ public ShellDecorator setOverlayColor( Color color, int alpha ) {
     setData( shell, OVERLAY_COLOR, overlay );
     return this;
   }
+
+  /**
+   * <p>
+   * Specifies the titlebar color of modal shells.
+   * </p>
+   *
+   * @param color the color to use for shell titlebar. Must not be <code>null</code>.
+   * @param alpha the alpha value of the color.
+   *
+   * @since 3.17
+   */
+  public ShellDecorator setTitlebarColor( Color color, int alpha ) {
+    whenNull( color ).throwIllegalArgument( "Color must not be null" );
+    when( alpha < 0 || alpha > 255 ).throwIllegalArgument( "Alpha must be >= 0 and <= 255 but was " + alpha );
+    RGB rgb = color.getRGB();
+    JsonArray overlay = new JsonArray().add( rgb.red ).add( rgb.green ).add( rgb.blue ).add( alpha );
+    setData( shell, TITLEBAR_COLOR, overlay );
+    return this;
+  }
 }