The scientific study of child witnesses has influenced both developmental science and jurisprudence concerning children. Focusing on the author's own studies, 4 categories of research are briefly reviewed: (a) children's eyewitness memory and suggestibility; (b) memory for traumatic events in childhood; (c) disclosure of child sexual abuse; and (d) experiences of child victim/witnesses within the legal system. Implications for psychology and for legal practice are discussed.