This paper provides results of a study which characterized women in science, aimed at identifying those factors thought to discriminate among males and females in the humanities, biological sciences, and physical sciences. The areas of spatial ability, attitude toward science, and rate of maturation were chosen as possible discriminating variables. Males and female undergraduate humanities and science majors (N=86) were given two Educational Testing Service spatial tests, and additional information was collected concerning major, science hobbies, number of previous science courses, and a short essay on feelings about pursuing a career in science. Included among the results of this study was that, regardless of sex, spatial ability and a positive attitude toward science are factors which influence a choice of career in science. (CS)