A person-centered approach was followed for the study of patterns in personality development in middle childhood through early adolescence. In a longitudinal study of 100 children, the "big five" personality factors--extraversion, agreeableness, conscientiousness, emotional stability, and openness--were assessed in person descriptions by teachers on the California Child Q-Set (CCQ) at the ages of 7, 10, and 12 years. Cluster analysis on these five personality dimensions in three measurement waves resulted in three clusters. The clusters were very similar to personality types found by Robins and others (1994) in American boys. Following the Robins study, Cluster 1, consisting of a nearly equal number of boys and girls, was called Overcontrollers; Cluster 2, consisting of mostly girls and a few boys, was called Resilients; and Cluster 3, consisting of mostly boys and a few girls, was called Undercontrollers. The clusters differed in ego-resiliency and ego-control as well as in level of the big five personality dimensions over the investigated age episode. Furthermore, the clusters differed on school competence, intelligence, and acceptance and rejection by classmates. Results indicated a remarkable similarity between the three cluster types to those found in the Robins study. (Author/DR)