This paper, which is a reworked version of the inaugural lecture of the Chair of Penology delivered on 24 May 1995 at the University of Edinburgh, sets out an account of the relationship between penology and criminology which reverses the conventional understanding of the relationship between these two disciplines. Instead of viewing penology as an applied sub-discipline of criminology, it is argued that criminological ideas should be viewed as part of the object of study of penological research, insofar as criminology comes to function within penal practices. This conception of penology is illustrated by an analytical account of contemporary penal policies and the role of criminological ideas within them. The analysis suggests that the character of recent crime control policy is not so much punitive as ambivalent. The social fact of high crime rates, together with the increasingly recognised limits of state action as a means of governing crime, have created a new predicament for policy makers and for politicians. The article identifies adaptive strategies and strategies of denial, as well as the different criminologies that accompany them, and outlines a Durkheimian account of social development that situates these developments sociologically.