This paper presents a unitary approach to emotion and emotion regulation, building on the excellent points in the lead article by Cole, Martin, and Dennis (this issue), as well as the fine commentaries that follow it. It begins by stressing how, in the real world, the processes underlying emotion and emotion regulation appear to be largely one and the same, rendering the value of the distinction largely for the benefit of analysis. There is an extensive discussion of how the same processes can generate emotions (i.e., are constitutive of emotion) and account for variability of manifestation of emotion in context (i.e., regulate them). Following an extensive review of many of the principles involved in emotion and emotion regulation, the paper presents implications for developmental study of infants and children, includes several methodological recommendations, and concludes with an analysis of the extent to which contemporary affective neuroscience contributes to the study of emotion and emotion regulation.