This is the age when children truly become social beings. Prior to the school-age years, children have primary formative relationships with their adult caregivers. In the preschool years, they develop friendships with other children, but are not unduly influenced by the inevitable crises of these relationships. In the school-age years, however, peer relationships become much more central. Entering this period, children have already mastered a rudimentary understanding of the minds of others, the difference between right and wrong, and some degree of frustration tolerance and impulse control. These critical skills continue to solidify in the school-age years, supporting the development of peer relationships. Children have internalized moral standards to some extent, and there is a basic concept of fairness and justice which persists even in the absence of an adult. Children have developed a repertoire of tools to manage conflict in peer relationships, such as sharing, compromising, helping, and seeing things from another’s perspective.