This chapter examines the powers of the police to stop and search people in the context of an initial discussion of police culture and discretion in general. The development of greater powers over the last 35 years since the Police and Criminal Evidence Act 1984 (PACE) was introduced is charted. The chapter considers whether stop and search is racially discriminatory; the constraints and controls on the exercise of discretion; and the impact of stop-search powers. It argues that the working assumptions based on ‘suspiciousness’—i.e. hunch, incongruity, and stereotyping on the basis of types of people, previous records, and so forth—still play as important a part in influencing the exercise of discretion as do legal constraints. This is all true even when responding to citizen reports of suspected offences.