Several objectively scored measures of fear of success and fear of failure have been designed in recent years, but there is little evidence that they measure two distinct, unidimensional constructs. The present study was undertaken primarily to answer two questions: Are fear of success and fear of failure operationally distinct? Do all fear of success measures tap a single unidimensional construct? Eight fear of success and fear of failure scales were administered to 415 male and female subjects, and the scores were intercorrelated. Results indicated that fear of success is not a unidimensional construct and that some of the measures of fear of success and fear of failure are highly related. Next, each scale was factor analyzed, and 37 new variables were created. These were in turn factor analyzed, and five highly stable orthogonal factors were obtained. One of these factors appears to be fear of success; another is clearly test anxiety (called fear of failure in the literature on achievement motivation). A third factor is concerned with sex-role-related attitudes toward success in medical school. A fourth seems to reflect neurotic insecurity, and the fifth has to do with the value of success. Indices of psychological well-being and psychosomatic illness related differently to each of the five factors. Implications and further questions are discussed briefly.Homer's research on fear of success (Horner, 1969a(Horner, , 1969b(Horner, , 1972(Horner, , 1974 has generated well over 100 research articles in the past few years. According to Homer (1969a), fear of success (hereafter FOS) is "the fear that success in competitive situations will lead to negative consequences" (p. 38). Taken by itself this definitional phrase is quite general. However, because Homer was primarily interested in a form of FOS that she thought was characteristic of females in American