What drives socioeconomic success within a society? This study analyzes how late childhood intelligence, parental socioeconomic background, and gender relate to multiple dimensions of adult socioeconomic success (i.e., education, occupational status, and income). A particular focus is placed on education, which is considered as both an indicator of socioeconomic success and a mediator of the relationships with the other dimensions. Randomly sampled participants (N = 5,292) in a German prospective longitudinal study were assessed for the first time at age 12 years in 1991 and for the last time as adults in 2009-10. Comparison of the effects of childhood intelligence and parental socioeconomic background revealed childhood intelligence to be the more powerful predictor of the 3 dimensions of later adult socioeconomic success. Education was the strongest predictor of both later adult occupational status and later adult income, and mediated most of the effects of childhood intelligence and parental socioeconomic background on later adult occupational status and later adult income. A gender income gap was apparent, with men reporting higher income, even when childhood factors and education were controlled. Education barely mediated any gender differences, but family-related structural factors (i.e., working part time and having children) explained much of the gender gap in income.