There's a lot of collaborating going on in the mystery genre. Whether it is bringing together several characters from different series to solve a crime, or authors working together on a novel, collaboration brings an interesting perspective to the story.
Some mystery authors who write more than one series will occasionally bring their characters together on a case. J.A. Jance united her Seattle detective J.P. Beaumont and Arizona sheriff Joanna Brady in Partners in Crime. Robert Parker has included both P.I. Sunny Randall and police chief Jesse Stone in Blue Screen and High Profile.
Philip R. Craig teamed up with William Tapply, combining their series and bringing together their characters J. W. Jackson and Brady Coyne in First Light, Second Sight, and Third Strike.
Another method of collaboration is simply two authors writing a novel together. Sometimes they use their own names and sometimes they create a pseudonym. Susan Wittig Albert and her husband, Bill Albert, have written a mystery series under the name Robin Paige. Charles Todd (Carolyn and David Todd Watjen) is a mother and son partnership. Ellery Queen was the pen name of Frederic Dannay and his cousin, Manfred Lee.
Other pairs of authors who have written some mysteries together include these husbands and wives: Aimee and David Thurlo, Bill Pronzini and Marcia Muller, and Jonathan and Faye Kellerman. Other family duos include Mary Higgins Clark and her daughter Carol Higgins Clark (Christmas mysteries), Susan Conant and her daughter Jessica Conant-Park (Gourmet Girl mysteries), and, most recently, Dick Francis and his son, Felix.
Finally, there are collaborations among many authors to create a serial novel, where each chapter is written by a different author. Two examples we have in our mystery collection are Naked Came the Phoenix and I'd Kill for That, both edited by Marcia Talley.