This report describes a study to review and interpret existing trend data on vocational education enrollments and teachers. In the first section purposes of the study, research questions, and methodology are defined. Section 2 presents documented historical and projected trend data on vocational education enrollments and staff, together with factors assumed to be influencing changes in vocational trends. These factors include demography, availability of staff, costs of vocational education, and available funds. Section 3 describes a vocational teacher supply/demand (VTSD) model, a system dynamics model which is explicitly casual but the structure of which is guided but not determined by historically observed relationships. (The model produces data paralleling historical trends in vocational education, but it allows the reader to understand the assumptions which produce the trend data.) These incomplete and tentative conclusions are summarized from the model output from the initial base run of the VTSD model: gradual end by the mid 1980s of rising numbers of secondary vocational enrollment, gradual decline in growth at the postsecondary level, and no serious shortages of vocational instructors into the next decade. (Twenty-two tables of trend data and 11 figures depicting model output are provided.) (YLB)