The Problem. This study investigated whether or not a structured career development program, using a mobile guidance unit and operating on a limited time schedule, could provide a feasible means for facilitating the career development of ninth grade students in the rural school setting. Project MACE. MACE stands for "Mobile Assisted Career Exploration." Project MACE was a study developed by the research office of the Utah State Board of Education and conducted by Utah State University. The study used ninth grade students in sixteen selected rural Utah high schools and in two rural southeastern Idaho schools. Design of Research. The specific objectives of the study were measured in the form of the following null hypotheses: There is no significant difference between experimental and control groups in terms of career attitudes as measured by the Vocational Development Inventory Attitude Scale. There is no significant difference between experimental and control groups in terms of career values as measured by the Occupational Values Inventory. There is no significant difference between experimental and control groups pre- and post-test estimates of their aptitudes and interests as measured by the Self Ranking Inventory of Aptitudes and Interests. Since this study is an evaluation of an educational program still in some state of development, it is a formative evaluation. The format for the study is a research and development model rather than a true experimental design. Population. Project MACE selected those schools which were considered representative of rural Utah high schools, It was decided that project MACE could accommodate about one thousand students during the school year. Sixteen schools were selected for the study. In addition, two schools in Southeastern Idaho were chosen as a control population. Observational Design. Three objective tests were given on a pre- and post-test basis to all of the students included in Project MACE. In addition, subjective data were gathered through student, parent and faculty questionnaires. Program.The treatment program was designed to give each student an opportunity to evaluate and discuss his aptitudes and interests. The student was then assisted in relating this information to various occupations and training possibilities. Each student learned how to use occupational information sources and was encouraged to investigate several occupations of his choice. All students were involved in group and individual counseling, including a joint session with their parents. The major focus of the counseling sessions was to assist students in making tentative career choices which were realishc and obtainable for them. To carry out the program, a counselor and occupational instructor were employed. Conclusions. Hypotheses one and three were both rejected as the data revealed differences at a statistically significant level. Career attitudes and knowledge of aptitudes and interests were positively influenced by the experimental program. Hypothesis two, concerning career values, was accepted for the values of salary, security and demand, and rejected for the values of prestige, interest and satisfaction. Sex differences were noted on all the evaluation instruments. Recommendations. The treatment program should be continued in schools needing the service on a continuous basis. Several possible avenues for future research were suggested. Among the more important were: (1) a replication of this study using urban schools and comparing the treatment conducted in a mobile facility versus the same program in a classroom setting; (2) a study of the independent teaching variables to determine which are most effective; and (3) a study to determine the long range implications of the treatment.