This study examines changes in expressed vocational choices made over an 18-month period by a sample of students who were each enrolled in one of 62 2-year institutions. Ability, interest, and family background measures were used as independent variables. Results indicated (1) that vocational choice changers were very similar to nonchangers in terms of the 23 independent variables examined; (2) that vocational choice change patterns varied widely among groups of changers; and (3) that there were very substantial differences in the choice changes made by males and females. Theoretical and practical implications of the findings are discussed. (Author)