There isn't a WPF-specific FolderBrowserDialog but the Windows Forms version should work fine. Just add a reference to System.Windows.Forms.dll and then create it in the usual way.

As a general rule, it's best not to put 'using System.Windows.Forms;' at the top of the file as this can lead to ambiguity errors when WPF has similarly named controls etc.

So, just fully qualify everything:

var fbd = new System.Windows.Forms.FolderBrowserDialog();
fbd.RootFolder = Environment.SpecialFolder.Personal; // or whatever 
string folder = null;
if (fbd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
   folder = fbd.SelectedPath;
}