This is the twentieth in the most prestigious series of annual volumes in the field of industrial and organizational psychology. The series provides authoritative and integrative reviews of the key literature of industrial psychology and organizational behaviour. The chapters are written by established experts and topics are carefully chosen to reflect the major concerns in both the research literature and in current practice. Continuing in the tradition of the series as a whole, this twentieth volume provides scholarly, up to the minute reviews and updates of work in a number of well established areas such as: mergers and acquisitions, burnout and health, and personality in industrial and organizational psychology. Emergent issues are also covered in chapters on social identity, emotions in organizations, the contribution of industrial and organizational psychology to ensuring safety in commercial aircraft, and the analysis of justice in human resource management decisions. Each chapter offers a comprehensive and critical survey of the chosen topic, and each is supported by a valuable bibliography. For advanced students, academics and researchers, as well as professional psychologists and managers, this remains the most authoritative and current guide to new developments and established knowledge in the field of industrial and organizational psychology. The contributors to Volume 20 include: Neal M. Ashkanasy, Australia; Claire E. Ashton James, Australia; Shlomo Berliner, Israel; Susan Cartwright, UK; Jose M. Cortina, USA; Naomi Ellemers, The Netherlands; Stephen W. Gilliland, USA; Don Harris, UK; S. Alexander Haslam, UK; Michael J. Ingerick, USA; Samuel Melamed, Israel; Layne Paddock, USA; Itzhak Shapira, Israel; Arie Shirom, Israel; Lauren Thomas, UK; and, Sharon Toker, Israel.