Joseph Campos, developmental psychologist at UC Berkeley, discusses his decades of research on how emotion develops in infancy, in an interview from Yale's Experts in Emotion series directed by June Gruber. Campos traces what drew him to the study of emotion, then walks through central discoveries from his career, including work on infants' emerging emotional responses and how these shape early development. The middle of the talk, running from roughly the five-minute mark to nearly seventeen minutes, covers the bulk of his research findings. He closes by describing where he sees the field heading next and offers advice for students considering a career studying emotion. The format is a structured, chaptered interview rather than a classroom lecture, but the content is substantive and specific to Campos's own research program in developmental psychology.