DAVID HEINEMEIER HANSSON is the creator of Ruby on Rails, an open-source web framework on which hundreds of thousands of web applications have been built - including Twitter. He is also Fried's business partner at 37signals and co-author of Rework.
37 SIGNALS is internationally renowned for its innovative web products, including Basecamp, Highrise and Campfire. Founded in 1999, 37signals has grown into a multi-million dollar company with over three million loyal customers. The company, based in Chicago, has been profiled in the Guardian, Time, Wired and Business Week.

JASON FRIED is the founder of 37signals, a privately held web-based software development company and the co-author of the international bestseller Rework. His motto is, 'It's simple until you make it complicated'.