Perseus Books Group is an American publishing company founded in 1996 by investor Frank Pearl. It was named Publisher of the Year in 2007 by Publishers Weekly magazine for its role in taking on publishers formerly distributed by Publishers Group West and acquiring Avalon Publishing Group.

In January 2007, Perseus Book Group purchased Avalon Publishing Group, the parent company of Carroll & Graf and Thunder's Mouth Press; the purchaser folded both imprints and stopped publishing books under those names in May 2007.

The Perseus Books Group currently has 12 imprints:

Before Avalon Publishing Group was integrated into the Perseus Books Group, it published on 14 imprint presses. In 2007, some of these imprints were integrated into the Perseus Books Group, while others folded or were sold to other companies. Perseus also sold one of their imprints in the restructuring process.
Avalon Publishing Group:

Perseus Books Group:

Books LLC is an American publisher and a book sales club based in Memphis, Tennessee.

Books LLC publishes print on demand paperback and downloadable compilations of English texts and documents from open knowledge sources such as Wikipedia. Books LLC's copy of English Wikipedia is republished by Google Books. Titles are also published in French and German respectively under the names "Livres Groupe" and "Bücher Gruppe". Books do include URLs of photos instead of the iconography of the original documents. According to the FAQ page: “We understand how annoying that can be for the reader. But our first priority has to be respecting copyright laws. In addition, the resolution of the online photos are not high enough to print in a book.”

In 2009, Books LLC and its sister imprint General Books LLC produced respectively 224,460 and 11,887 titles.

In brackets: kind of material published and sold.

Adam L. Penenberg (born July 27, 1962) is a U.S. investigative journalist best known for his role in the affair surrounding the The New Republic reporter Stephen Glass in 1998.

In the summer of 1998, Penenberg, then a reporter with Forbes magazine's online arm, Forbes Digital Tool, came upon a story in TNR about a Silicon Valley firm who was hacked by a teenager, then hired the hacker as a security consultant. Amazed that TNR had somehow managed to scoop Forbes, Penenberg tried to verify it. Penenberg could not find any evidence that the company, Jukt Micronics, even existed. He also could not verify any of the events that Glass claimed resulted from the hacker's hiring, such as a radio spot from concerned Nevada state officials or several joint state efforts to combat hacking. After an internal TNR investigation determined Glass had made up the story out of whole cloth, TNR fired him.

As of 2005 Penenberg is an assistant professor of journalism at New York University. He is also a freelance writer for Fast Company, the New York Times, Forbes, Wired News, and Playboy. His non-fiction book Tragic Indifference: One Man's Battle With the Auto Industry Over the Dangers of SUVs which deals with the biggest product liability case in history, the Ford and Firestone controversy, was published in 2003 and is currently being made into a movie.