The American Psychological Association, in the late 1940s, began work to establish a code of ethics to include and address the needs of members in scientific and applied fields. Out of the ethics work emerged a set of standards for evaluating psychological tests. Four categories, or types of validity, were identified: content, predictive, concurrent, and construct. In subsequent years, predictive and concurrent were combined in a single category labeled criterion validity. The resulting three categories of validity, sometimes called the holy trinity, having survived nearly 40 years of use, are now entrenched concepts in test construction and evaluation. Current trends in the conceptualization of test validity dismiss these three categories as separate entities, but old habits die hard, as apparently do old ideas. This paper reviews the emergence of validity as a unitarian concept, and discusses current views with particular attention to consequential validity. The current theory that delineates the superordinate nature of construct validity and dictates that all lines of validity evidence ultimately point to the construct is reviewed. Consequential validity refers to actual and potential outcomes of test use. It is a controversial concept in that where and when attention to the social and political ramifications of test use should be addressed is arguable. (Contains 24 references.) (SLD)