The evaluation design, which prescribes when and from whom to gather data, is described as significant because it can lend credibility to evaluation results. The objectives of this booklet are to aid the evaluator in: choosing a design; putting it into operation; and analyzing and reporting the data. Examples include both formative and summative evaluation designs. Chapter titles are: (1) An Introduction to Evaluation Design; (2) The Elements of Design; (3) Designs--an Overview; (4) Three Control Group Designs; (5) Two Time Series Designs; (6) The Before-and-After Design; (7) A More Complex Design: Analysis of Variance (ANOVA); and (8) How to Randomize. Several of the chapters conclude with short blbliographies. (MH)