The purpose of this study was to empirically validate subjects' classification of 11 attributions (mood, skill, knowledge, chance, effort, competence, help, ability, task, bias, luck) according to dimensions of locus, stability, controllability, predictability, and globality. The sample of 200 subjects (100 males and 100 females) consisted of 50 undergraduate education majors, 50 graduate education majors, 50 undergraduate psychology students, and 50 naive lay individuals (over 35 years of age) who had never attended a college or university. Attributions were placed on separate pages of a questionnaire, followed by a random ordering of the five dimensions presented on 7-point scales. The results indicated that subjects' dimensional assignment of five of Weiner's (1979) original eight attributions differed significantly from Weiner's assignment of those attributions. In addition, there were significant differences in the classification of attributions according to predictability and controllability. In 62% of the possible instances, the results of this study were in agreement with the theoretical assignments of attributions from the literature.A theory of classroom motivation (Weiner, 1979(Weiner, ,1980 has emerged that attempts to articulate cognitions and emotions in causal attributions. Causal factors other than Weiner's (1979) original four (ability, effort, task difficulty, and luck) have been documented (Elig & Frieze, 1975,1979, such as stable effort, other people, mood, personality, and physical appearance. Still other causal factors continue to emerge (see Cooper & Burger, 1980).Although the term luck is most frequently used in the causal-attribution research literature, chance may well be a less confusing term, particularly with respect to the stability dimension. Chance is clearly random and unstable. However, when one speaks of luck, one can think of either the randomness of the concept or the trait aspect, which is indicated in the phrase "he is a lucky person."Similarly, ability may be consistently categorized as stable. But if one defines ability as skill, knowledge, or competence, The authors are grateful to Bernard Weiner for his encouragement and his many suggestions.Request for reprints should be sent to Theodore A.