Brazil has experienced a broad expansion of education in the last few decades, but inequalities in educational access are still high for people of different socioeconomic statuses as well as by gender and race. Using data that covers higher education expansion from 1982 to 2006 in Brazil, this dissertation investigates the consequences of this expansion for existing social inequalities in the country. Using 22 cross-sections of the Brazilian Household Survey (PNAD), it investigates changes over time in access to postsecondary education, the horizontal stratification of the postsecondary system between private and public sectors, and market responses to changes in the distribution of postsecondary diplomas. Using data from the National Examination of Courses from 2003, it investigates other types of horizontal stratification within the Brazilian postsecondary system. The main findings are that (a) despite expansion, the influence of social origins on access to higher education remained strong in Brazil, and even increased, while access to secondary education was greatly improved, as a sign that the competition for the available educational openings is transferring to higher levels; (b) there is horizontal stratification within higher education in Brazil by institutional sector, by fields of study and by the quality of course programs, differentiating the type of education received; and (c) changes in the educational distribution of the labor market reduced average wage differences across sectors of economic activity, but also reduced returns to a postsecondary diploma in the sectors that witnessed the largest increases in the number of postsecondary education graduates. Current educational policies in Brazil are changing the ways in which the expansion of higher education is occurring. Future research should take into account the impact of these policies for the trends detected in this dissertation. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]