This is the 20th volume of the International Review of Industrial and Organizational Psychology. In keeping with previous volumes in the series we have commissioned chapters on a range of topics at the cutting edge of the industrial,work, and organizational psychology field, from some of the world’s leading researchers. A number of central topics covered in the present volume ( ut,the psychology of mergers and acquisitions, and emotions in the workplace) have been surveyed in earlier volumes in the series,but such is the scale of developments currently taking place in these areas that we considered it timely that these topics should be revisited