James Patrick "Jim" Baen (b. 1943) started his publishing career, appropriately enough, in the complaints department of Ace Books after stints in the Army, at CCNY, and in Greenwich Village in the 1960s working as the manager of a folk music coffee shop (a "basket house").
He soon moved to take Judy-Lynn del Rey's place at Galaxy magazine, and succeeded Ejler Jakobsson as editor of Galaxy and If in 1974 after a brief trip back to Ace to be assistant Gothics editor. While at Galaxy he published such authors as Jerry Pournelle, Charles Sheffield, Joanna Russ and John Varley, and was nominated for several Hugo Awards. He returned to Ace to head their science fiction line, working with publisher Tom Doherty.
When Doherty left to start Tor, Baen shortly followed and started the SF line there. In 1983 he had the opportunity to start his own independent company, Baen Books, distributed then and now by Pocket Books/Simon & Schuster. Baen Books has established a large readership, publishing books by authors such as David Weber, John Ringo, Eric Flint, David Drake, Lois McMaster Bujold, Elizabeth Moon, Mercedes Lackey, Larry Niven and many more.
Jim Baen is very active on the baen.com website, "Baen's Bar," where his interests in evolutionary biology, space technology, politics, military history, and bad puns are discussed along with science fiction.
Jim Baen has also started an experimental web publishing business called webscription.net and also the Baen Free Library