From the 1980s to the present, educational accountability in the United States has grown dramatically. Such accountability in U.S. school districts, although driven primarily by external demands, has internal manifestations as well. The chapter traces the historical development of internal evaluation in American school districts, then highlights four current forms of internal evaluation (standardized testing programs, evaluations of externally funded programs, support for school improvement planning, and evaluation capacity building), along with a brief description of the decade-long development of internal evaluation in one school district. The unique features of internal evaluation in educational settings are highlighted, and the chapter concludes with implications of current practice for the continuing development of internal educational evaluation. © Wiley Periodicals, Inc., and the American Evaluation Association.