This is the second of five series which Barry Letts produced consecutively and Terrance Dicks was the script editor.

Nicholas Courtney and John Levene continue their roles of Brigadier Lethbridge-Stewart and Sergeant Benton, while Richard Franklin makes his first appearance as Captain Mike Yates.

Fernanda Marlowe makes appearances in The Mind of Evil and The Claws of Axos as Corporal Bell.

Bernard Kay makes his fourth and final appearance in the show as Caldwell in Colony in Space.

Colony in Space was the first serial set away from Earth since The War Games at the end of Season 6, and came about as a result of producer Barry Letts' feeling that the Earthbound stories of the Doctor's exile were too limiting in terms of potential plotting.