"In the United States, demographic statistics since the 1970s have shown a varied definition of "families', resulting in a departure from traditionally homogeneous housing needs. Changes in housing and land costs, as well as consumer expectations, have created a gap between median family income and housing affordability. For families below the median income level, affordable housing choices are extremely limited, especially in terms of house design. Often, low and middle income families must settle for older houses or those designed by home builders that are economically expedient but lacking in their ability to satisfy users' individual needs and preferences. We have designed a computer-based participatory design system for the creation of affordable housing designs to make it possible for laypersons to create their own individualized plans. Elderly people and young couples who need adult-centered houses and single parents with children who need child-centered houses were our target groups. Our research included the following five stages: 1) We identified a target group of 30 respondents within the affordable housing market; 2) We collected spatial data by using an open-ended schedule focusing on the respondents' manipulations of three dimensional models of house and furniture components. Additionally, we collected social data using a structured questionnaire that recorded social characteristics, household task behaviors, personality variables, and housing! neighborhood preferences; 3) We built a data bank of respondents' completed house plans and analyzed them using space syntax analysis; 4) We used multiple regression analyses to explore connections between person's spatial preferences and their social characteristics, behaviors and values; 5) We have designed an interactive computer system to build multiple designs based on options that are available within the program. Hence, laypersons can design and plot their own plans by using the menu-driven computer program - - Participatory Affordable Design System for Housing (PADS) Participatory Affordable Design System for Housing, is the interactive software system based on the commercial CAD software called AutoCAD that we are developing through this research effort. The software will work in conjunction with the AutoCAD software to provide an interactive graphic environment for the generation of affordable house plans. This system will provide producers of manufactured housing, mobile home builders, as well as, small home builders with a tool that can expand and improve the variety of their products by responding to individual customer's needs. We are assuming that when people have choices, they have increased control of their lives. Choice and control increase satisfaction among them, and their houses become special personal spaces. Thus, a participatory system will benefit people in the affordable housing market by providing a variety of house designs that are attuned to individual needs and preferences. Such a system will be judged successful by the variety of affordable house designs it can generate, and more importantly, how well these designs suit individual needs and preferences. This product has the potential to influence growth within the affordable housing market. This paper will describef the participatory process involved in the creation of the designs, as well as the integration of the participatory techniques within the CAD system. During this first stage pilot project we collected and analyzed the user data, and built the interactive computer program. We plan to begin field testing (PADS) in the near future."