This paper describes four commonly used designs in equating test scores. These designs are: (1) single-group; (2) random-group; (3) equivalent-group; and (4) anchor-test. Each design requires that its data be collected according to specific guidelines. Three of the four methods are illustrated through hypothetical examples. All four methods try to equate test scores from equally reliable and parallel measures. Although the anchor-test design is not as simple to implement as the other designs, it is one of the most popular equating procedures. (Contains 2 tables, 1 figure, and 10 references.) (Author/SLD)