The document summarizes urbanization in less economically developed countries (LEDCs) and its consequences. It describes that over 1 billion people live in urban slums, with the highest concentration in Asia where 60% of the world's slums are located. In the slums of Manila, Philippines, over 40% of the urban population live in dense, unsanitary conditions. The document profiles three families living in difficult circumstances in Tondo, one of the poorest and most overcrowded slum areas of Manila, and discusses the problems faced by slum communities including inadequate and unsafe housing, lack of basic services, and insecure land tenure.