Know-How Exchange : Advertising/PR

I've been asked by a client to create a message map for their seven different audiences. The objective is to create a simple template for the client to use to craft internal and external advertising/collateral materials. Of course the message will fit within the mission statement, audience needs, etc and lays out proof points for each message. I am asking for examples of how you've done this. Any thoughts or examples you have are greatly appreciated!