The Australian Institute of Criminology has spent a number of years working with crime prevention agencies across Australia reviewing large-scale programs that involve the delivery of varying activities directed at the prevention of crime. Taken as a whole, this experience has shown that, despite good intentions and aspirations to evidence-based practice, both the level and quality of evaluations have been limited by several practical challenges. In turn, this has hampered efforts to develop a body of good quality Australian evidence about what is effective in preventing crime and what is required in order to deliver effective interventions. Using previously unpublished data collected as part of the reviews of two national Australian crime prevention programs, the authors examine the practical factors that impact on evaluation and make a number of important recommendations for the evaluation of projects delivered as part of large-scale community crime prevention programs. The authors argue that rather than persisting with traditional approaches that encourage local organisations to undertake potentially expensive and time-consuming evaluations of their own work, program managers and central agencies must become more proactive and increasingly innovative in their approaches to evaluation.