diff --git a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/WorkbenchMessages.java b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/WorkbenchMessages.java
index 60029ee..31c0a02 100644
--- a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/WorkbenchMessages.java
+++ b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/WorkbenchMessages.java
@@ -23,6 +23,10 @@
 	private static final String BUNDLE_NAME = "org.eclipse.ui.internal.messages";//$NON-NLS-1$
 
 
+	public static String ThemeChangeWarningText;
+
+	public static String ThemeChangeWarningTitle;
+
 	public static String BundleSigningTray_Cant_Find_Service;
 
 
diff --git a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/dialogs/ViewsPreferencePage.java b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/dialogs/ViewsPreferencePage.java
index 462761c..67f8821 100644
--- a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/dialogs/ViewsPreferencePage.java
+++ b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/dialogs/ViewsPreferencePage.java
@@ -16,6 +16,7 @@
 import org.eclipse.e4.ui.css.swt.theme.IThemeEngine;
 import org.eclipse.e4.ui.internal.workbench.swt.E4Application;
 import org.eclipse.e4.ui.model.application.MApplication;
+import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.jface.preference.PreferencePage;
 import org.eclipse.jface.viewers.ArrayContentProvider;
@@ -51,7 +52,6 @@
 	private ComboViewer themeIdCombo;
 	private ITheme currentTheme;
 	private String defaultTheme;
-
 	private Button enableAnimations;
 	private Button useColoredLabels;
 	
@@ -139,6 +139,10 @@
 	 */
 	@Override
 	public boolean performOk() {
+		if (!getSelection().equals(currentTheme)) {
+			MessageDialog.openWarning(getShell(), WorkbenchMessages.ThemeChangeWarningTitle,
+					WorkbenchMessages.ThemeChangeWarningText);
+		}
 		engine.setTheme(getSelection(), true);
 		IPreferenceStore apiStore = PrefUtil.getAPIPreferenceStore();
 		apiStore.setValue(IWorkbenchPreferenceConstants.ENABLE_ANIMATIONS,
diff --git a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/messages.properties b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/messages.properties
index 8e9f204..ae8346d 100644
--- a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/messages.properties
+++ b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/messages.properties
@@ -491,7 +491,8 @@
 #---- General Preferences----
 PreferencePage_noDescription = (No description available)
 PreferencePageParameterValues_pageLabelSeparator = \ >\ 
-
+ThemeChangeWarningText = A restart is required for the theme change to take full effect. 
+ThemeChangeWarningTitle = Theme change 
 # --- Workbench -----
 WorkbenchPreference_openMode=Open mode
 WorkbenchPreference_doubleClick=D&ouble click