Extensively revised to reflect modern views of program implementation, this volume introduces the variety of functions served by implementation studies and the roles played by qualitative and quantitative data. The reader is shown the importance of assessing how a program design works in actual practice--and is given the planning tools and procedures to make assessment happen. The evaluator′s role in documenting, describing, observing and assessing how a program is implemented is covered in detail. Step-by-step guidelines are provided for identifying key program processes and arrangements for assessment, for selecting optimal strategies for conducting the assessment, and for developing and analyzing questionnaires, interviews, observations, and program records.