Anger is a basic human emotion which typically occurs when control of outcomes is lost or goals are thwarted. Anger expressions are observed even in 2- to 8- month old infants in such contexts. Yet, individual differences in the pattern of anger/frustration are seen. Some infants show only anger when control of an expected event is disrupted, others show a mixture of anger and sad expressions, while still others show only sadness. The project will examine empirically two aspects of the early anger response. First, the project will study the conditions under which loss of control of outcomes elicits anger early in life. Of particular interest is how the anger response may vary when loss of control is only partial. Secondly, the project will explore the relation of early parental responsiveness and temperament factors to individual differences in infant anger expression. Thus, the research will establish the basic dynamics of early anger in response to frustrating events, including its origins in socialization and constitutional factors.