"Diane..." - The Twin Peaks Tapes of Agent Cooper, is a two-sided cassette audio released on October 1, 1990 by Simon & Schuster. It compiles many of the recorded diary entries of Dale Cooper to his assistant Diane that had been featured in the first season and the first episode of the second one, along with new specially-recorded entries written by Scott Frost. It has been re-released as an audiobook.

Some entries from the original broadcasts are not included on the tapes. The tape begins with a monologue taking place before the pilot in which Cooper discusses his impending trip to Twin Peaks and continues with the initial monologue heard in the pilot, then eventually concludes with the day when he was shot.

For his work, Kyle MacLachlan was nominated for a Grammy Award for best spoken-word performance.