CADE-21 The 21 st Conference on Automated Deduction 4th International Verification Workshop VERIFY’07 Editor: Bernhard Beckert Bremen, Germany, July 15–16, 2007 CADE-21 Organization: Conference Chair: Michael Kohlhase (Jacobs University Bremen) Program Chair: Frank Pfenning (Carnegie Mellon University) Workshop Chair: Christoph Benzm¨ uller (University of Cambridge) Local Organization: Event4 Event Management