This thesis will be a study of those physical aspects of urban environments which have a bearing on the physical solution of housing for laboring classes in the U.S.A. and Latin America. An attempt will be made to define the nature and extent of the low income family housing problem according to varying physical stages of urbanization. Within a physical framework, adequate low income family housing types and placement will be proposed. PART ONE of this study approaches the problem analytically. The assumption is made that stages of urbanization differ in the U.S.A. and Latin America. An analysis of these assumptions will provide some conditioning aspects with which to face the housing problem. These stages are the contexts of the housing problem. PART TWO of this work establishes the hypothesis that the prototypes of the housing solution depend on the comparative stages of urbanization. A matrix model will be proposed for comparison and analysis of the recommended solution at a given point in time. The subject of the Part Three is the hypothesis that the location and density of the typical housing should be derived from the physical forces of the local context and its stage of urbanization. In reality, economic and social factors and their related political aspects are also important considerations, but this paper will concentrate on physical factors only. In Part Four Houston, ( the fifth largest American city ), and Antofagasta, ( the fifth largest Chilean city ), two cities which are similarly related to their respective nations, will be examined as two different physical contexts that condition their physical housing solutions. The thesis will be completed by a diagramatic presentation of prototype designs for Houston and Antofagasta that illustrate the text's principles.