Book excerpt: This book features cutting edge research on the theory and measurement of affect dynamics from the leading experts in this emerging field. Authors will discuss how affect dynamics are instantiated across neural, psychological and behavioral levels of processing and provide state of the art analytical and computational techniques for assessing temporal changes in affective experiences. In the section on Within-episode Affect Dynamics, the authors discuss how single emotional episodes may unfold including the duration of affective responses, the dynamics of regulating those affective responses and how these are instantiated in the brain. In the section on Between-episode Affect Dynamics, the authors discuss how emotions and moods at one point in time may influence subsequent emotions and moods, and the importance of the time-scales on which we assess these dynamics. In the section on Between-person Dynamics the authors propose that interactions and relationships with others form much of the basis of our affect dynamics. Lastly, in the section on Computational Models of Affect, authors provide state of the art analytical techniques for assessing and modeling temporal changes in affective experiences. Affect Dynamics will serve as a reference for both seasoned and beginning affective science researchers to explore affect changes across time, how these affect dynamics occur, and the causal antecedents of these dynamics.