Part I. Nonstandard Markets: 1. Matching markets: theory and practice Atila Abdulkadiroğlu and Tayfun Sönmez; 2. The economics of Internet markets Jonathan Levin; 3. Discussion of 'matching markets: theory and practice' Yeon-Koo Che; Part II. Contracts: 4. Contracts: the theory of dynamic principal-agent relationships and the continuous-time approach Yuliy Sannikov; 5. Dynamic financial contracting Bruno Biais, Thomas Mariotti and Jean Charles Rochet; 6. Comments on contracts Johannes Hörner; Part III. Decision Theory: 7. Ambiguity and the Bayesian paradigm Itzhak Gilboa and Massimo Marinacci; 8. Temptation Bart Lipman and Wolfgang Pesendorfer; 9. Comments on 'behavioral' decision theory Ran Spiegler; Part IV. Communication/Organization: 10. Giving and receiving advice Joel Sobel; 11. Organizational economics with cognitive costs Luis Garicano and Andrea Prat; Part V. Foundations Epistemics and Calibration: 12. Strategies and interactive beliefs in dynamic games Pierpaolo Battigalli, Alfredo Di Tillio and Dov Samet; 13. Calibration: respice, adspice, prospice Dean Foster and Rakesh Vohra; 14. Discussion of 'strategies and interactive beliefs in dynamic games' and of 'calibration: respice, adspice, prospice' Wojciech Olszewski; Part VI. Patents: Pros and Cons for Innovation and Efficiency: 15. Revisiting the relationship between competition, patenting, and innovation Philippe Aghion, Peter Howitt and Susanne Prantl; 16. Mechanisms for allocation and decentralization of patent rights Hugo Hopenhayn, Gerard Llobet and Matthew Mitchell.