The objectives of this booklet are to provide suggestions, procedures, and rules of thumb to aid the evaluator in using achievement tests in program evaluation. It also discusses some of the theories underlying the procedures for developing and selecting achievement tests and interpreting their results. Each of the six chapters offers advice on one area of achievement testing. Chapter 1 deals with deciding what to measure and how much time and effort to invest in testing activities. Chapter 2 describes the types of achievement test data available, and their possible uses. Chapter 3 presents a Table for Program-Test Comparison, and gives a step-by-step procedure to calculate indices of test appropriateness to the program being evaluated. Chapter 4 is a guide to resources which aid in custom designing tests, and contains an annotated list of test item and objectives banks and a list of testing services, which design and score tests. Chapter 5 discusses test reliability and test validity. Chapter 6 deals with test interpretation and score reporting. A summary of common item construction errors is appended. (MH)