In the first part of this paper, the current status of criterion-related validity research in the field of career development assessment is analyzed. It is shown that the results of intermediate and long-term follow-up studies--in contrast to studies in the same educational setting--provide only little evidence for the assumption that career maturity in school has substantial impact on later career adjustment. In this analysis it is pointed out that several factors are responsible for this situation, particularly deficiencies in the use of career maturity measures as predictors and shortcomings in the selection of criterion measures and in theory. In addition, it is suggested that further factors like self-concept orientation in choice and realization of career plans might function as mediating variables between career development in school and career adjustment. In the second part of the paper the results of two follow-up studies aimed at testing the empirical appropriateness of these assumptions, conducted on 223 apprentices and 172 university students, are reported. The findings correspond mainly with the theoretical expectations. Self-concept orientation appeared as the most important intervening variable. The consequences of the results for further research in this field are discussed. (Author)