Implementing a P3P 1.0 Client

Client can be implemented as browser, proxy, plug-in, java applet, JavaScript, etc.

Can be entirely server side
Can be part of an infomediary service, shopping tool bar, automatic form filler, etc.

Look for link to P3P policy and fetch policy with HTTP GET request
Parse policy and take appropriate action

Display symbol, play sound, prompt user, etc.
Action can optionally be based on user preferences
Action can optionally allow data to be automatically filled into form or transferred from electronic wallet