The paper traces the evolution of psychiatric care for children from an intrapsychic orientation to a new conceptual perspective provided by systems theory and the accompanying relational formulation of conflict. The interdisciplinary process prevents a challenge to professionals' collaboration and respect for other fields and mandates critical self-monitoring. Chaos results from a clash in interdisciplinary evaluation between the traditional linear behavioral perspective and a higher order circular and more relational point of view. Findings of an internal causal approach to a depressed 13-year old are contrasted with a family systems approach which highlighted the need for family psychotherapy to establish clear generational boundaries, help resolve old grief and anger issues and enhance the self-worth of individual members. (CL)