Providing affordable housing has been a long-standing issue for governments of most countries. In an attempt to address the issue, affordable housing programs have been introduced with the aim of improving household's access to housing, as well as sustain their wellbeing. This paper reports on a study of the activities of affordable housing program (AHP) in Papua New Guinea (PNG), using Port Moresby as a case. It also reports a potential strategy for improving effectiveness of the program. Data was collected from interviews involving private property developers, building contractors, and an official of the National Housing Corporation. Documents related to PNG housing sector and AHP were also reviewed. The results show that the criteria used for measuring housing affordability is lacking in PNG. Low-income households do not benefit from the AHP, which focuses mainly on homeownership scheme. Role of the public sector and private sector in the provision of affordable housing is not clear. Most private developers would like to supply more houses to the housing market. However, the developers face challenges such as shortages of secure land, high cost of materials for constructing houses, and lack of trunk infrastructure. If the aim is to improve effectiveness of the AHP, there is a need to develop criteria for measuring housing affordability and to introduce affordable housing schemes that meet low-income household's preferences and demand. It is necessary to reduce housing costs by making more secure land available for development, providing trunk infrastructure, and sourcing building materials locally. The sustainability of AHP should be given due consideration during the planning and design phase. The findings could assist urban development managers and planners in designing a more effective AHP in PNG.