This paper summarizes some of the basic concepts in test equating. Various types of equating methods, as well as data collection designs, are outlined, with attempts to provide insight into preferred methods and techniques. Test equating describes a group of methods that enable test constructors and users to compare scores from two different forms of a test. Horizontal equating is performed between two different versions of a test, and vertical equating is performed on tests across difficulty levels. The most basic of the equating methods is linear equating, which assumes that the two tests to be equated differ only in means and standard deviations. Equipercentile equating considers scores to be equivalent if the percentile ranks corresponding to the scores on two forms of a test are equal. Item response theory equating is a viable alternative to more conventional methods of equating. It uses item characteristic curves to describe the relationship between a score on a test and the item difficulty and item discrimination. While it is beyond the scope of the paper to go into great detail, some issues related to test equating are considered. More detailed readings are recommended. (Contains 2 figures and 17 references.) (Author/SLD)