How to avoid setting Focus / Tab on Grid ?

Hi,

I have a ListBox inside a normal WPF <Grid/>. When I move around with Arrow keys or Tab, I get the Grid selection (see dotted border around the listbox in the attached image). I tried setting the following in the Grid XAML, but no luck -

KeyboardNavigation.IsTabStop="False"

OR

FocusManager.IsFocusScope="False"

Any idea how to get around this issue ?