How create thick border around a group of shape but thin between them

Nov 26, 2013 at 8:33 PM
on my map ( french map) with 95 shape , one for each department, i wan't have a thick border around a group of department (region) but a thin border between departement on the same region. i don't know how do that, is it possible ?

sorry for my english
Nov 27, 2013 at 6:36 PM
You need to look at categories and unique values.
Here's an example:

Nov 27, 2013 at 9:24 PM
that works fine as i whish