This paper is a discussion of a 4-year research and development project dealing with the cluster concept approach to vocational education. The concept is a form of vocational education that prepares the individual to enter into gainful employment in a number of occupations which have sufficient commonalities in human requirements and kinds of work to permit a high degree of mobility within the cluster. Its principal mission was to provide job entry skills and second level skills in a series of related areas. This movement was prompted by the increasing mobility of people, the need for mobility within an industry, the need to adopt to technological changes, and the problem of selecting one's life work. The first phase of the project was devoted to a number of important probes and developments, the second phase to teacher education and the preparation of curriculum materials, the third to implementation and further development through field testing and evaluation at the secondary level, and the fourth to implementation and development through testing and evaluation including placement and followup of subjects. (Author/GEB)