CHES2007, theninthworkshoponCryptographicHardwareandEmbeddedS- tems, was sponsored by the International Association for Cryptologic Research (IACR) and held in Vienna, Austria, September 10-13, 2007. The workshop - ceived 99 submissions from 24 countries, of which the Program Committee (39 members from 15 countries) selected 31 for presentation. For the ?rst time in the history of CHES, each submission was reviewed by at least four reviewers instead of three (and at least ?ve for submissions by PC members, those now being limited to two per member) and many submitted papers have received...