In recent years, the concept of public-private partnerships has increasingly become central to crucial areas of service provision to offenders. However, the development of this approach has placed little emphasis on empirical findings regarding the viability of partnership arrangements and has not clarified some important conceptual and philosophical questions concerning the nature and purpose of partnerships. The results of two recent systematic studies of different aspects of the work of the probation service, in which the concept of partnership was central, indicate that much more work needs to be done on such issues of policies based on partnership are to be both effective and sustainable. Specific issues include coordination, monitoring, responsiveness to local issues, time lines for planning and implementation, pooling of resources, and impacts on probation services. 11 references (Author abstract modified)