To test aspects of a theory of the role of personality and gender on the development of vocational interests and their subsequent effects on adult occupational choices, the authors of this study examined associations among childhood personality traits, gender, and occupational environments more than 40 years later. Participants (N = 587) were assessed on the Big Five by their teachers when the participants were between 6 and 12 years old. In middle-age (late 40s), the participants reported their occupation. Holland's (1997) RIASEC vocational types (Realistic, Investigative, Artistic, Social, Enterprising, Conventional) were used to characterize the job environments of reported occupations. Childhood Openness/Intellect and Conscientiousness, but no other Big Five traits, were associated with occupational environments. For the most strongly sex-typed work environments, associations with Openness/Intellect were moderated by gender. These findings suggest that the roots of the strongest gender-stereotyping effects in occupations may be found not only in the social factors associated with gender but also in the individual differences of children related to Openness/Intellect. (Contains 3 tables, 3 figures, and 1 footnote.)