The City of Johannesburg (CoJ) and other South African cities have sough to implement inclusionary housing policies toward catalyzing spatial restructuring in post-apartheid human settlements and the provision of affordable housing. These policies include rules or planning techniques that mandate or offer incentives to private developers to include affordable or social housing as part of their market-driven developments. The CoJ adopted its first inclusionary housing policy in February 2019, which requires private developers to preserve a percentage of 30% for affordable housing. However, the implementation of inclusionary housing is relatively new in South Africa and limited research on the social, economic, and spatial effects of related policies have been undertaken, including their ability to stimulate the provision of affordable housing. The aim of this research is to evaluate the effectiveness of the CoJ inclusionary housing policy in this regard. The study employed a qualitative research approach, using semi-structured interviews as a data collection instrument involving relevant municipal officials and private developers situated in the study area. Findings indicate that there are significant challenges in the implementation of the policy, including potential negative effects on the feasibility of market-orientated developments subject to affordability requirements, and a disjuncture between policy objectives and potential outcomes. However, there is a cross-stakeholder consensus regarding the need for inclusionary housing policy in the municipality with specific reference to its potential to foster integration and housing affordability. Recommendations include increased collaboration in the implementation of the policy calculator intervention, improved monitoring of developer adherence to affordability requirements, and the continuous engagement between public and private stakeholders toward the improvement of the policy and its directives.