Interest in the development of affect regulation in early childhood has focused until recently chiefly on two issues: the development of “impulse control” in children and the clinical implications of individual differences in such emotional control. In charting the growth of children's control of their own anger, frustration, distress, or excitement, researchers have given most of their attention, justifiably, to developments in the second and third years of life. To parents, the development of their children's ability to argue rather than resort to physical violence, to wait rather than wail, to contain their impatience rather than explode in tantrums is clearly a major achievement during these years. Yet in this period children's emotional behavior and their powers of influencing their own and others' affective states expand far more broadly than a focus solely on the “damping down” of extremes of anger, distress, and excitement would imply. Children's displays of uninhibited anger or frustration do indeed change markedly, increasing sharply in the second year and decreasing in the third, as Frances Goodenough's classic study in the 1930s showed (Goodenough, 1931). But if we include in our notion of “affect regulation” children's interactions with others - that is, if we see affect regulation not simply as a private “homeostatic” mechanism but also as a feature of children's relationships with others - then this period of the second and third year must be highlighted even more as one of the major developmental changes in children's control and influence over their emotional states.