--- - |2 Abstract In this article, I recount my history of research with great apes. From the beginning, the idea was to compare apes to human children, with an eye to discovering facts relevant to describing and explaining processes of human development. The research went through three more or less distinct stages, focusing on communication and social learning, social cognition and theory of mind, and cooperation and shared intentionality. I conclude by identifying problems and prospects for comparative research in developmental psychology. - Child Development Perspectives, Volume 12, Issue 3, Page 189-193, September 2018.