Drawing on Holland's vocational theory, Schneider's Attraction-Selection-Attrition model, and the Big Five/narrow traits model of personality, the present study identified key BigFive and narrow personality traits that both distinguish scientists from members of other occupations and related these to their career satisfaction. A sample of 2,015 scientists had significantly higher levels of openness, intrinsic motivation, and tough-mindedness, and significantly lower levels of assertiveness, conscientiousness, emotional stability, extraversion, optimism, and visionary style than a sample of nonscientists (n = 78,753). Seven traits were significantly correlated with the career satisfaction of scientists: agreeableness/ teamwork, assertiveness, emotional stability, extraversion, openness, optimism, and work drive. Based on these results, a psychological profile of scientists was presented. Findings were discussed in terms of the functional value and person-occupation fit of these traits for the work of scientists. Implications were described for the recruitment, selection, management, and promotion of scientists, as well as their training, development, coaching, counseling, and mentoring.R&D Management 42, 1, 2012.