This investigation examined the dimensions of developmental timing, subtype, and severity of maltreatment and their relations with child adaptation. The 814 children who participated in a summer day camp, 492 of whom were maltreated and 322 of whom were nonmaltreated comparison children, were assessed by camp counselors on their internalizing and externalizing symptomatology, aggressive, withdrawn, and cooperative behavior, and on personality dimensions of ego resiliency and ego control, and were rated by peers on disruptive, aggressive, and cooperative behavior. The severity within each subtype of maltreatment and the developmental period in which each subtype occurred were examined through hierarchical regression analyses. Additionally, children with similar timing or subtype patterns were grouped to explore diversity in outcomes. Results highlighted the role of severity of emotional maltreatment in the infancy-toddlerhood period and physical abuse during the preschool period in predicting externalizing behavior and aggression. Severity of physical neglect, particularly when it occurred during the preschool period, was associated with internalizing symptomatology and withdrawn behavior. Additionally, maltreatment during the school-age period contributed significant variance after earlier maltreatment was controlled. Chronic maltreatment, especially with onset during infancy-toddlerhood or preschool periods, was linked with more maladaptive outcomes. The implications of measuring multiple dimensions for improving research in child maltreatment are discussed.