Children with early onset conduct problems are at risk for long lasting psychosocial problems, which is especially true for children who also dis-play Callous-Unemotional (CU) traits. Very few studies have investigated the co-development of conduct problems and CU traits across time and none have done so in preschool years. In this study, we examined joint tra-jectories/groups of conduct problems and CU traits and examine whether temperamental and personality dimensions are associated with stability and change of co-occurring conduct problems and CU traits during early childhood. A longitudinal data base (the SOFIA study) was used in which children (n = 2121) were followed longitudinally at ages 3–5 years, 4–6 years, and 5–7 years. The Child Problematic Traits Inventory (CPTI) was used as the measure of psychopathic traits. Results suggested that children exhibiting high conduct problems and CU traits over time were charac-terized by deviations in temperament (fearlessness and low levels of easy temperament) and psychopathic personality dimensions. Children with decreasing or increasing conduct problems and CU traits were character-ized by marked decreases and increases respectively on temperamental and personality dimensions. In contrast, children with high conduct problems but low CU traits over time were characterized by less deviation on tem-peramental and personality dimensions compared to all other groups of children except the children with low conduct problems and low CU traits. In conclusion, specific temperamental and personality dimensions seem to be closely associated with stability and change of conduct problems and CU traits during the preschool years. Temperamental and personali-ty dimensions associated with the development of conduct problems and CU traits are changeable over time and may constitute key dimensions in preventive efforts.