Persuasive technology is the general class of technologies that purposefully apply psychological principles of persuasion - principles of credibility, trust, reciprocity, authority and the like - in interactive media, in the service of changing their users' attitudes and behavior. Only one year ago, in 2006, the first international conference in this area, PERSUASIVE 2006 was hosted in Eindhoven. The conference was entirely geared towards communicating the progress made in the area of persuasive technology, and towards presenting recent results in theory, design, technology and evaluation. It brought together a wide range of research fields, including social psychology, HCI, computer science, industrial design, engineering, game design, communication science, and human factors, and the formula worked: plans for a follow-up were made immediately upon its conclusion. PERSUASIVE 2007, the second international conference on persuasive technology, was hosted by Stanford University, April 26-27. The program featured a large number of presentations, both oral and in poster format, on new findings, new conceptualizations and designs, and new reflections on persuasion through technology. Sponsored by the National Science Foundation, this conference featured the best new insights into how video games, mobile phone applications, and Web sites can be designed to motivate and influence people.