Imprint of Penguin Group (USA), Inc., and part of the Berkley Publishing Group together with the New American Library (NAL) imprint.
Berkley Books began as an independent company in 1955. It was established by Charles Byrne and Frederick Klein, who were working for Avon and formed "Chic News Company". They renamed it Berkley Publishing Co. in 1955. They soon found a niche in science fiction works. They were bought out in 1965 by G. P. Putnam's Sons and became their paperback publisher.
In 1982, Putnam bought Grosset & Dunlap and Playboy Press, and the Ace and Playboy paperback lists were added to Berkley.
Berkley is now an imprint of Penguin Group (USA), which purchased Putnam in 1996, and prints in mass-market paperback, trade paperback, and hardcover formats.