A brief overview of the history of the scientific study of the child in Canada is provided in this paper. Discussion begins with an account of the scholarly interests and activities of James Mark Baldwin, who brought modern psychology to Canada, and Frederic Tracy, who objected to child-centered approaches to child rearing. The remainder of the paper focuses on the professional activities and ideas of William Emet Blatz, Canada's first really modern child psychologist. Blatz' role in the success of the nursery school established in the early 1920's at the University of Toronto and the research conducted and theories developed there are briefly described. Blatz, it is noted, produced a theory of personality development (called "security" theory) centering on a concept of mental health and how it could be attained. The importance of research on the Dionne Quintuplets in persuading the University of Toronto to create an Institute of Child Study was also indicated. Concluding discussion focuses on elements of Blatz's psychology, including functionalist, cognitive developmentalist, and biological orientations; the idea of "selection" (i.e., choice behavior) as the essence of consciousness; and the interaction of selection, motivation, goal-seeking, emotion, and the active child's appraisal of the situation--all of which influence learning. Brief mention is made of Blatz's views about the psychological needs of infants and preschool-aged children, the characteristics and outcomes of parenting that meet those needs, and Blatz's scholarly production. (RH)