Abstract: In response to a deepening housing affordability crisis and an impending economic downturn, governments in Australia recently introduced a host of policy initiatives and legislative mechanisms in an effort to boost the supply of affordable housing. In NSW, most proposals for affordable housing development in recent years were uncontroversial, but there was fierce and highprofile opposition from community members in a small number of Local Government Areas (LGAs). Here, opposition campaigns received widespread media coverage and gained significant political traction. While there is an extensive inter-disciplinary literature on NIMBYism and the factors that underlie community opposition to affordable housing, particularly in the US context, almost no research has sought to examine the reasons that community opposition escalates in some places but not others. Through a mixed-methods retrospective case study of an ‘extreme’ instance of community opposition to affordable housing development in the Western Sydney LGA of Parramatta, this paper looks at how and why community opposition to affordable housing escalated between 2009 and 2011, addressing this gap in knowledge. The paper finds that the fierce opposition to affordable housing development in Parramatta was based partly in prejudice against affordable housing residents and issues to do with the planning assessment process, but may also have been fuelled by political manoeuvre.