Evaluation is discusses as a primary element in the change process. Defined as a procedure for obtaining data to make decisions, evaluation is regarded as a recurring determination of the extent to which objectives have been reached, within a four-stage sequence of research, development, diffusion, and adoption. A conceptual scheme for viewing the role of evaluation is explained and distinctions are made between evaluation procedures applicable to decision making on Federal and State administrative levels and procedures applicable to decision making on the local level. Six recommendations are made for the implementation of evaluation of projects developed under the ESEA Act of 1965. (JK)