Community based probation practice and development is concerned with specific forms of Probation Service supervision described here as community probation work, and other, non-supervisory, practices described as community work and crime prevention work. For both sets of practices the probation fieldwork team acts as the frame of reference where primacy is given to enhanced service delivery systems, and where the locality is a referral source and a resource, not simply a remote situational context. The study begins by describing the Probation Service's philanthropic origins, the merger of criminal justice and social work, and the legislative base for, and function of, subsequent supervisory developments. It then explores the variety of ways in which the "community" has recently emerged as an additional focus for Probation intervention. The empirical study into the work of a new community Probation Team reveals the complexities of translating policy intentions into working community based probation practices. The bulk of the empirical work is concerned with exploring the ways in which this inner city team defined, implemented and sustained its practices. Evidence is provided for claiming that the implementation of community based probation practice requires an explicit acknowledgement not only of organisational imperatives, but of other more significant and interdependent factors. External legislative requirements, internal administrative factors and interactional forces (symbolised by client/worker exchanges), the local setting and the national social context, are regarded as particularly significant. At a theoretical level, and drawing on some of the insights offered by interactionism and functionalism, the study examines the creation of a new community Probation Team, as one societal reaction, amidst others, to a social problem, namely the 1981 urban disturbances in Brixton. The empirical work suggests that a three-fold conceptual model based on social control, social welfare, and social justice considerations provides a valuable theo;retical instrument for analysing community based probation practice and development. The study ends by drawing together these theoretical features, as well as examining some policy and organisational implications for the Probation Service arising from such work.