Preface; 1. Recent progress in interpreting the nature of the near-Earth object population W. Bottke, A. Morbidelli and R. Jedicke; 2. Earth impactors: orbital characteristics and warning times S. R. Chesley and T. B. Spahr; 3. The role of radar in predicting and preventing asteroid and comet collisions with Earth S. J. Ostro and J. D. Giorgini; 4. Interior structures for asteroids and cometary nuclei E. Asphaug; 5. What we know and don't know about surfaces of potentially hazardous small bodies C. R. Chapman; 6. About deflecting asteroids and comets K. A. Holsapple; 7. Scientific requirements for understanding the near-Earth asteroid population A. W. Harris; 8. Physical properties of comets and asteroids inferred from fireball observations M. D. Martino and A. Cellino; 9. Mitigation technologies and their requirements C. Gritzner and R. Kahle; 10. Peering inside near-Earth objects with radio tomography W. Kofman and A. Safaeinili; 11. Seismological imvestigation of asteroid and comet interiors J. D. Walker and W. F. Huebner; 12. Lander and penetrator science for near-Earth object mitigation studies A. J. Ball, P. Lognonne, K. Seiferlin, M. Patzold and T. Spohn; 13. Optimal interpretation and deflection of Earth-approaching asteroids using low-thrust electric propulsion B. A. Conway; 14. Close proximity operations at small bodies: orbiting, hovering, and hopping D. J. Scheeres; 15. Mission operations in low gravity regolith and dust D. Sears, M. Franzen, S. Moore, S. Nichols, M. Kareev and P. Benoit; 16. Impacts and the public: communicating the nature of the impact hazard D. Morrison, C. R. Chapman, D. Steel and R. P. Binzel; 17. Towards a program to remove the threat of hazardous NEOs M. J. S. Belton.