Separating Server and Client Code

Our server will be interacting with a sql server database and would prefer to have all server logic in separate dlls that the client knows nothing about - hopefully just a shared RPC communication interface between client (game player) and the server. My question is, how do people do this in conjunction with RPC?

It seems the for the client to contact the server via RPC, it needs the server object with the RPC calls (including it's behavior and dependencies), to make the call.

Can I somehow put the RPC calls on an interface, then have the client calls those somehow, and the server implement the rpc interface?

Cheers, Lars