It is generally thought that evaluation originated with the civil service exams that were administered in ancient China. However, modern evaluation and, of particular importance to this article, evaluation standards, originated in the United States. Why this occurred is part of a larger question about the development of social and educational programs in the United States and the demand for effective and efficient evaluation of them. A number of thorough introductions to the origins of program evaluation in the United States have been published. These highlight the development in the first half of the twentieth century of methods to describe and assess educational and social program outcomes through the precise specification and measurement of objectives. They also describe the rise of federal, state, and local interest in funding educational programs and social programs in the second half of the twentieth century. Several factors--the large number of new social and educational programs in the United States, the development of measurement and assessment technology, the belief in human and societal improvement, and the demands for accountability regarding public expenditures--set the stage for the development of standards to guide program evaluations. The development of standards for evaluating programs and projects grew out of situations and circumstances that were characteristic of, if not unique to, the American experience. This article describes the background and history of the Joint Committee's Program Evaluation Standards.