如何在XAML中显示本地化文本

I've got a WPF application which I need to localize for Spanish. I've read the MSDN docs and I'm left confused. This is complicated in that our company has a suite of three programs that work together (one is a Windows service, one is a web application and the third is my WPF application) and we've decided to build one resource DLL that contains the localizable strings for all three products.I've got a WPF application which I need to loca