Abstract
This article reviews the use of the broad category of internalizing disorders and data on young children using this definition. It also reviews the emerging support for more specific internalizing diagnoses in very young children. The current empiric database on nosology and treatment of mood and anxiety disorders in young children is examined, and a clinical case example is included. Identification of recent advances in the understanding and treatment of anxiety disorders in young children and areas in which future studies are needed also are explored.