The authors investigated the effects of attention to novelty, fear-anxiety, and age on 3 measures of conduct problems. They found several main and interaction effects. The results indicated the presence of the hypothesized 3-way interaction for 2 dependent measures (i.e., conduct problem, socialized aggression); the 3rd dependent measure (i.e., conduct disorder) approached significance (p = 0.07). Participants who were older, had low attention to novelty, and high fear-anxiety generally had the highest conduct-problem scores among 8 comparison groups. Older students with high attention to novelty and low fear-anxiety had significantly lower conduct-problem scores that were unremarkable. The findings are congruent with J. Gray's (1987) theory of behavioral activation and inhibition, and the results support R. C. Eaves' (1993) integrated theory of human behavior, which postulates that the level of attention to novelty, fear-anxiety, and age interact to produce individuals with conduct problems. (Contains 8 tables and 1 figure.)