The purpose of this paper is to present the results of an analysis of intragenerational ethnic mobility of Aboriginal peoples using a data source that allows direct estimation of the phenomenon in Canada for the first time: a linkage between the 2001 and 2006 Censuses of Population. Intragenerational ethnic mobility, or change in the self-reporting of Aboriginal identity over the course of life, contributed significantly to population growth for the Métis and for North American Indians living off Indian reserves in recent decades. However, the estimations that have been published up to now are all based on an indirect measurement and thus provide only limited insight into the associated characteristics. The descriptive and multivariate analysis the authors propose in this paper shows that Aboriginal population gains due to ethnic mobility are actually the result of multidirectional flows related to certain key characteristics, such as mixed ethnicity. The paper also explores the effects of ethnic mobility on the sociodemographic composition of Aboriginal populations, with their geographic distribution for example being modified as a result of the changes in self reporting of identity from one census to the other.