In the present report three separate studies of childhood depression were conducted. First, the internal structure of the Child Depression Inventory (CDI), with 216 children representing various ethnic groups with equal numbers of boys and girls, was evaluated through a factor analysis and by various internal-reliability measures (e.g. split-half reliabilities, Pearson correlations of each item to the total score). Four factors were established and internal reliability of the scale proved to be high. The relationship of the factor structure of the CDI to Kendell's Type A and B categorization of depression are discussed. In Study 2 the relationship of demographic variables to the CDI using the same group of children described for Study 1 was employed. Evaluating the characteristics of depression across age, sex and so on in children has not been frequently studied, and was deemed appropriate for the present investigation. Age proved to be a significant factor in depression scores although race and gender did not. With respect to age, older children tended to display more symptomatology. Comparisons of depressed children to nondepressed children also showed that age was a factor in the obtained scores, and range of severity in both groups. Depressed children differed from nondepressed children on all 27 items indicating that all the items on the CDI seem to be measuring a unitary concept. Study 3 compared CDI scores to a measure of social behavior, the Matson Evaluation of Social Skills with Youngster (MESSY). Seventy-six children (36 girls and 40 boys), ages 4–10 yrs ( X ̄ = 7) were evaluated. Appropriate Social Skills was negatively correlated with childhood depression, and Inappropriate Impulsive/Assertiveness was positively correlated with depressive features described under the factor Guilt/Irritability. The implications of these data for further research on assessment, differential diagnosis and evaluation of treatment research are discussed.