This report examines the logic that underlies projection methods and applies that logic to data describing vocational teacher needs for 1978 through 1982. (The report addresses the demand for vocational education teachers only, not for other personnel such as counselors, prevocational teachers, and so on.) The report is organized into three sections. The first section contains a description of the techniques used to examine the past and to project the future demand for vocational teachers. In the second section, a critical assessment is made of the methods and data used to generate the projections for enrollments and teachers. The third section contains a brief analysis of the kinds of activities that, when carried out, would improve the adequacy and accuracy of the projection statistics. (The analysis concerns demand for teachers only and does not address the philosophy of teacher needs.) (KC)