Clinicians often encounter children who present with an extensive array of interacting behavior problems that are imbedded in complex social environments occur with medical complications and disabilities, and are influenced by multiple interactive causal relations.  Interventions based on psychiatric diagnoses, non-empirically based interventions, and empirically guided interventions that are poor fits to the child are insufficient bases for intervention decisions.  The interventions with the maximum benefit for the child are those that are based on a science-based approach to clinical assessment, match treatment mechanisms of action with the variables that affect the behavior problems, and are sensitive to dimensions of individual difference.