<Window x:Class="SimpleStyles.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="SimpleStyles" Background="#F8F8F8"> <ScrollViewer> <WrapPanel> <HeaderedItemsControl Header="GroupBox"> <StackPanel> <GroupBox Margin="8" Header="This is the Header" Width="200" > <Border Height="100" /> </GroupBox> </StackPanel> </HeaderedItemsControl> </WrapPanel> </ScrollViewer> </Window>