This paper discusses vulnerability dynamics due to housing and neighbourhood expansion. The vulnerable situation arose out of separate individual decisions developing housing areas haphazardly. These decisions determine the efficiency of the final patterns of flows and emerging land uses. Using water consumption over 15 years as a representation of housing expansion, we argue that that the accessibility, or lack of, to basic amenities such as clean water is impacted by the pattern of housing expansion. The extent of the vulnerability is dependent, among others by impacts on livelihoods, accessibility to a range of basic infrastructures, and the effectiveness of different institutions and organizations in providing social infrastructures, acting as an important buffer or defence in the face of shocks and stresses. The core question guiding the research behind this paper is how patterns of vulnerability have change in the period of 1992 – 2007 for over 350 housing estates that made up about four hundred thousands people living in the study area. The paper uses the Seremban Municipality area, situated in the State of Negeri Sembilan in Peninsula Malaysia, and currently experiencing vibrant economic, social and physical developments, to illustrate the housing and neighbourhood dynamics. This paper presents preliminary analysis of findings that gathers views from urban planners, managers, developers, and residents on the vulnerability of the housing areas. Using a complexity approach to develop a better understanding of the planning and current status of changing housing vulnerability, the paper also presents a series of maps of changing housing vulnerability.