Community-based settlement is an important component in the dynamics of Third World urbanization. It consists of lower-income, self-help housing characterized by occupant-builders who act together in their collective best interests. It stands in contrast to the more common settlements of individuals who act singly in their own best interests. While studies of individualistic settlement of independent family units abound, no empirical studies have been conducted on community-based settlements. This doctoral dissertation research is a field-based study that will compare two individualistic and two community-based settlements in Mexico City and Ciudad Juarez in order to explore differences in occupant-builders' design motives, the resultant housing designs, and subsequent levels of housing consolidation. Data for the study will be collected by means of participant observation, selected informant interviewing, heuristic elicitation "games," and research evaluation of buildings. This research will provide valuable information for urban geographers, planners and developers, and architects about the expression of the social dynamics of self-help housing in the development of urban landscapes. It will contribute to our knowledge about the provision of adequate housing for thousands of families who are moving from rural areas to rapidly growing cities in developing countries throughout the world. The project also will provide an excellent opportunity for a promising young scholar to continue to develop independent research skills.