Juvenile justice program managers need to determine the effectiveness of the programs they operate. However, it is not uncommon for an evaluator of a program to determine, once the evaluation is underway, that the program is not ready for evaluation. This briefing paper, sponsored by the U.S. Department of Justice, Office of Juvenile Justice and Delinquency Prevention introduces program managers to the concept of Evaluability Assessment (EA). The concepts and ideas of EA are important for a program manager to understand and consider prior to having an evaluation conducted. EA determines whether a program has the basic foundation for an evaluation to take place. Having an EA improves a future evaluation by formalizing the agreement between the evaluator and decisionmakers on what is important in the program, anticipating evaluation problems, and smoothing the overall process. The paper describes an EA, determining whether the program is ready for evaluation, how to perform an EA, and how to ensure that the programs are evaluable. Once an EA is conducted, one of two conclusions can then be drawn: the program is ready for an evaluation or the program is not ready for an evaluation. References and appendix