Mack Reynolds, was born as Dallas McCord Reynolds.

As an pulp science fiction magazine author, he was published in Galaxy and Worlds of if. Popular in the 1960s, his stories were often set in utopian societies and had reformist themes. He was the first to write an original novel based on the TOS TV show that came out in hard cover and written for a young adult audience.

Reynolds was born in Corcoran, California. After his parents moved to Baltimore with him, they became active Marxists in the Socialist Labor Party. In the Second World War, Reynolds trained to be a Marine, but ended up in the US Army. In the 1950s, Reynolds lived in many different countries around the world, including some in Eastern Europe and Northern Africa, Japan and Mexico. Around this time Reynolds left the Socialist Labor Party. It has been suggested that his hard-left political background influenced his fiction writing, laden as it is with revolutionary ideas, and utopias. This is in contrast to one of the other earlier novelizers, James Blish who held more right wing views. He died in San Luis Potosi, Mexico, in 1983 after cancer surgery.

He wrote under numerous pen names, some of them variations of his birthname, others like Todd Harding, Mark Mallory and Bob Belmont, completely different. A compilation of his work, The Best of Mack Reynolds, was published in 1976.