Abstract: There is a broad assumption in Australia that planning processes should facilitate efficient land and housing markets. However, the planning drive towards medium density housing (MDH) has triggered widespread local resistance. This has led to new scrutiny of mechanisms for public participation in planning and efficiency of third party objection and appeal rights (TPOAR). This paper focuses on the latter. Policy debate around TPOAR often focuses on whether and how TPOAR distort housing markets. There are also concerns around how residents’ opposition to MDH affects, and potentially inhibits, the achievement of compact city and social housing objectives. On the other hand, TROAR are seen as an important mechanism to facilitate community engagement in planning systems, and to provide greater accountability in development approval processes. These debates have intensified in Australia in recent years. A Productivity Commission Inquiry into development approval processes has argued for reforms to TPOAR (Productivity Commission, 2011). Through the Council of Australian Governments, all States and Territories are currently exploring more streamlined development approval processes that will limit the application of TPOAR in housing development. The Federal Government has already worked with State and Territory Planning authorities to remove TPOAR in the roll-out of its 5 billion dollar Social Housing Initiative. Despite this, there is little data documenting the extent to which TPOAR inhibits housing supply and whether these rights are accessed evenly across the population. While the idea that objections and appeals by resident groups in inner suburbs are inhibiting the development of MDH is a powerful narrative in Australian cities, there is still no city-wide evidence of the extent to which third party appeals are causing delays. In this paper we show that this appetite for policy reform has so far, preceded the evidence base. The impacts on accountability and participatory planning aims are also uncertain. The paper first sets out the tensions between compact city policies and resident perceptions of MDH. Second, the paper defines TPOAR and situates these rights within the wider planning process. While permit applicants (first parties) can also appeal planning decisions, this research is concerned with third parties only. While TPOAR are traditionally associated with participatory planning aims, this section shows TPOAR are positioned ambiguously in terms of greater public participation. The third section shows that in spite of these uncertainties, enthusiasm to limit TPOAR on the grounds of enabling housing supply has characterised policy reform in Australia and elsewhere.