The dynamic competition among innovative concepts, materials, methods and products that has characterized most consumer industries has not been fully effective in the business of housing. Although evolutionary progress has been made over the decades, the structure of the housing business, the existing institutions, the regulatory procedures and other factors have discouraged rather than encouraged modernization and improvement consistent with our overall technological, social, economic and political progress. The paper will describe the results that are being obtained in the United States from an overall approach aimed at overcoming these obstacles to more rapid modernization. This effort, under the title `Operation Breakthrough', aims at encouraging a competition among ideas, methods, materials, and a restructuring of the regulatory and other elements of the housing business. The goal is improved housing for all of our people in a good living environment. The paper describes changes that have already taken place in the building regulatory area. New approaches which are being taken by many of the States, as compared to the more traditional, local jurisdictional practice, and to some still existing State regulatory practices, are described. In addition, the paper describes the technological effort that is required to evaluate new ideas in building systems. The major point to be made in this connexion is that extensive testing, as well as research and development, is required to solve problems associated with new systems when they are designed to meet certain performance criteria. Established practices have the advantage of experience and past public and professional acceptance. The new systems must be encouraged in order to arrive at a position that can indeed be considered competitive with the traditional approaches. Detailed technical analysis is indicating the problems that exist and that must be solved with a wide variety of technologies that have not yet been put into full practice in the United States. The result would be a fuller, more dynamic competition among a broader variety of building approaches. But the emphasis is not on the buildings alone. Rather, it is on total community design and development. Mixed functions and mixed building types combined into a total residential community are also being carefully considered in their design. This part of the Operation Breakthrough programme is intended as a model for general urban growth patterns. Examples of the approaches being used in, and technical advances being tested for, Operation Breakthrough are presented.