The research summarized in this report was stimulated by the need for an objective, standardized measure of vocational maturity which would provide an empirical referrent for the conceptual terms of vocational development. The instrument constructed for this purpose is the Vocational Development Inventory (VDI), consisting of the Competence Test designed to assess the cognitive components of vocational maturity, and the Attitude Scale designed to operationally define the conative elements in vocational maturity. The Attitude Scale is the only part of the VDI that has been developed and extensively investigated over the past 8 years. To further study the Attitude Scale, the Vocational Development Project (VDP) was established to implement a program of four different, but interrelated types of research, including survey, technique, theoretical, and applied. A data bank has been maintained by VDP to collate and analyze the research findings and to disseminate them periodically to facilitate further research. From the research conducted thus far, it can be concluded that the Attitude Scale is a widely applicable, reliable, and valid measure of vocational maturity and that it enters into relationships with a number of variables indicating that it operationally defines the concept of vocational maturity. (Author/SB)