Call of Cthulhu RPG is a 39-book series with 41 primary works first released in 1981 with contributions by Keith Herber, William Deitze, Sandy Petersen, Lynn Willis, Chris Williams, Kevin Ross, Scott David Aniolowski, Fred Behrendt, J. Todd Kingrea, Mark Morrison, Mike Szymanski, Owen Guthrie, Sam Johnson, Chaosium Inc., Dennis Detwiller, Adam Scott Glancy, John Tynes, Shane Ivey, John H. Crowe III, Michael Cisco, Denis Detwiller, Jeff Moeller, Rebecca Strong, Charles Engan, Jan Engan, Bruce Ballon, Matt Harpold, Paul Carrick, Monte Cook, Alan Bligh, Keary Birch, Paul Fricker, Mike Mason, John French, Warren Banks, Greg Stolze, Kenneth Hite, Sarah Newton, Dave Blewer, Alex Bund, Adam Crossingham, Mathew Pook, Lynne Hardy, Bill Bodden, Greg Stolze , Dennis Detwiller, Allan Gooda ll, Shane Ivey, Dave Blewer,, Jeffrey Moeller, Stephanie McAlea, Scott Dorward, Simon Brake, Brian M. Sammons, Oscar Rios, Yurek Chodak, Tadashi Ehara, Harry Henderson, Charlie Krank, Steve Perrin, Greg Stafford, Anders Swenson, Inc Staff Chaosium, Jesse Hawkins, Joshua O'Connor, Reuben Saunders, Chad Bowser, Ilya Sadchikov, Chris Birch, Yuri Kalugin, Sergey Kataev, and Benjamin Wenham.