This descriptive study examined the perceptions of a national sample of school psychologists in the United States regarding their perceived knowledge, preferred roles, and training needs in the prevention and treatment of nine prominent child and adolescent internalizing disorders. The results indicated that participants perceived the prevention of all nine internalizing disorders to be an appropriate role for school psychologists, and that they perceived the school-based treatment of particular disorders, such as school phobia/refusal, to be an appropriate role as well. A majority of the sample reported the need for some or significant additional training in all nine internalizing disorders. Limitations of the study and needs for future research are discussed. (Contains 3 tables.)