Police corruption is unquestionably one of the worst forms of corruption, as it can become a serious security issue and undermine a state's legitimacy.

This research review brings together the most informative scholarly and practitioner contributions on the subject in recent decades. It covers major aspects of police corruption, including its significance and impact, public perceptions, the causes of corruption and the problem of police culture. It details the situation in selected countries, and explores how and with what success they have addressed the problem.