how do use a class from another project?

I am developing a thick client and a web client for a piece of functionality
for my website. The main class lives in a thick client app and has ongoing
development done to it. I would like to use that class in my web app. How
can I do it? I would like to be able to reference the project in case I
want to debug into the class, and also be able to deploy the release version
when I copy/deploy to the server.

Is this possible?

Thanks.


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