While growing up, children experience a range of emotions that change with development and environment. Although all young children experience sadness at times, a main characteristic of young children is their ability to experience joy and excitement in pleasurable childhood activities. When a child seems perpetually sad and no longer seems interested in previously enjoyed activities, the child may be showing signs of early onset depression. Children who are depressed are at increased risk for a wide range of social, psychological, physical, and achievement-related problems. Two previous studies have established the validity of early onset depressive syndrome in preschoolers, confirming the need for treatment during the preschool period. This study will specifically adapt parent child interaction therapy (PCIT), a proven effective treatment for preschool disruptive disorders, for use in preschoolers with depression and will include an additional component to focus on emotion development (ED). The study will evaluate the effectiveness of PCIT-ED in treating depression in preschool children.