>I'm developing an app that I will then send to my client's site.
>
>I could change the connection string in the app.config before I build my setup, but then I have to keep
>changing it each time I create a new build.
>
>What's the best way to manage this?

Why not put that in your settings file which ends up being an xml? If you are using some form of password in your connection string, you may need to encrypt it and decrypt it in your application.
Tim