<p>Emotional communication is conceptualized as a dyadic process, involving both an expresser (the “encoder” who conveys an emotion) and a perceiver (the “decoder” who interprets it). Research to date has mostly focused on decoders’ interpretation of expressions, yielding a robust understanding of perceiver characteristics that can affect the perception of emotion (e.g., clinical status, personality traits, cultural background) and of the association between specific nonverbal cues and the impression of emotion (e.g., how movements of specific facial action units are perceived). However, extant research has largely ignored or undervalued <i>encoder</i> characteristics that may influence the production of emotion. The current review paper argues that there are important inter-individual differences in the nonverbal expression of emotion. Specifically, we review variability in the use of nonverbal cues to encode emotional expressions as a function of age, sex/gender, sociocultural background, personality, and clinical status. We consider these individual differences across multiple contexts (e.g., spontaneous and posed) and communication channels (e.g., face, voice, body), and propose methodological approaches to systematically investigate encoder effects in emotion research. Overall, we contend that it is necessary to consider expresser-related effects in research on emotional communication to garner a fuller understanding of the processes underlying both emotion production and perception.</p>