<p>In this paper, we consider a number of issues regarding crime prevention and criminal justice. We begin by considering how crime is measured and present both general and specific evidence on the level of crime in a variety of countries. Crime is pervasive and varies substantially across countries. We outline the arguments for some public role in crime prevention, enforcement, prosecution, defence, adjudication and punishment. We consider the relative roles of the public and private sectors in crime control and criminal justice. We discuss various measures for the effectiveness of the criminal justice system. We conclude by suggesting some potential areas for research. </p>