Well, in the traditional sense {not using computer programs and such}, a record producer oversees everything to do with a session--guiding, supervising the recording, working with the production budget....and they oversee the mixing and mastering of the final recording. Yeah, I imagine they would be responsible for hiring session musicians too. I'm sure the good ones {George Martin, etc.} can also have a lot to do with arranging the songs to be recorded. And I think that they can also affect the outcome of the entire project {album} as a whole--as far as molding it as how they envision the album to sound.

Hey, "never say never"....