How can the server command the client program?

[bpk1970]

Hi all,

I am busy designing a simple client-server application using WCF (in VB 2008 with .NET 3.5)

The server application is hosted on my computer, with 2 client programs communicating with this local server application. The client programs call upon the server using a proxy.(method).

My question is: How can the server application "command" the client programs to take a certain action (specifically update the screen display after certain server events)?

Any advice would be greatly appreciated.

thanks,

bk