Six of the ten essays in this collection (Lombardi, Villamarin, Chance, Greenow, Robinson, and Cook) were originally presented at a Special Session during the 43rd International Congress of Americanists, held in Vancouver during August, 1979. Jointly organized by David J. Robinson and Juan Villamarin, the session was designed to bring together a group of individuals who had been working on the changing population of colonial Spanish America from various disciplinary perspectives, to facilitate an exchange of information and ideas, and to promote the further investigation of significant research questions. The paper of Brian Evans was presented at the same Congress, in another session, but given its purpose and content it was thought to provide an ideal complement to several papers in the present collection.