Literature on childhood friendship is quite diversified, focusing on various aspects (social, emotional and cognitive, etc.) revealing the complex nature of the subject. This study aimed at investigating different aspects of friendship in children in order to contribute to the formulation of a theoretical model forunderstanding friendship as a complex system of relations. Forty children aged seven to ten years, participants of the “Projeto Caminhando Juntos” (Cajun), in the city of Vitoria, were interviewed. This project offers several courses for children and adolescents from six to seventeen years old enrolled in schools in the city of Vitoria and aims to integrate children socially, avoiding them to stay on the streets, promoting physical education, moral and social children from disadvantaged communities. The results refer to friends network (including the best friend), space and time, activities and communication with friends, psychosocial processes (social support, competition, aggression and reconciliation), cognitive and affective processes (perception of friends and relationship and friendship and emotions) and the development of friendship. These aspects were discussed in light of their possible integration into a theoretical model of childhood friendship. We conclude that wide theoretical models of friendship and interpersonal relationships are necessary to guide research in the area.