A model incorporating both academic and nonacademic factors as determinants of productivity was tested with samples of physical and biological scientists, social scientists, and humanists taken from the 1972-73 American Council on Education survey of faculty at U.S. institutions of higher learning. Considerable variation was found in the process determining productivity both across the broad disciplinary categories as well as within categories when article and book productivity are compared. The relative influence of the disciplinary content and attributes of scholars on productivity was also examined. The analysis considered 17,399 faculty holding conventional appointments at universities or four-year colleges. The gender, race, marital status, and socioeconomic status of scholars were included in the analysis along with the following academic characteristics: years of experience, academic rank, tenure status, doctoral degree, time involved in obtaining this degree, number of grants received, and measures of commitment to research versus teaching. It is suggested that the decisive edge that physical and biological scientists enjoy over social scientists and humanists in article productivity is largely the result of the nature of work or a favorable disciplinary milieu, while the lower rate of productivity among humanists is more heavily determined by their attributes. References are included. (SW)