The development of a survey instrument for measuring the cognitive association of sex, love, and marriage (SLM) is reported. The SLM scale was tested in two phases with two distinct data sets. The first data set comprised the responses of 321 undergraduates at a New England state university. In this first phase, the specific item composition of the scale was determined, and initial reliability and internal consistency were established. The second data set included the responses of 835 undergraduates from three U.S. universities: a Northeastern state university, a Southwestern state university, and a Northwestern state university. In this second phase, additional reliability information was obtained, and the issue of construct validity was explored. By analysis, we judged that the SLM scale is, as expected, significantly related to extramarital sexual attitudes, premarital sexual attitudes, premarital sexual behavior, religiosity, and current relationship involvement. The theoretical significance of SLM association and the possible uses of the SLM scale as a research tool are discussed.