Brisbane, Australia will host the Olympic and Paralympic Games in 2032—the first to be contractually obliged to be Climate Positive. This commitment can be achieved through a combination of two levers: emission reduction measures and carbon offsets. The objective of this study is to determine which combination of these levers is likely to maximise sustainability and its social, economic, and ecological dimensions. Based on these dimensions and the perspective of technology determinism, a novel sustainability assessment model is developed. Then, through a document analysis, this study uses emissions data to analyse and evaluate three different combinations of carbon offsets and renewable energy. Results showed that a higher reliance on carbon offsets resulted in poorer sustainability outcomes for this mega-event. The most sustainable scenario, involving large-scale investment in renewable energy infrastructure, involved significant cost implications but is likely to create greater legacy outcomes. Key recommendations include improving the governance and socialisation of Climate Positive delivery, and increasing partnerships with the private sector. Doing so will help enhance the authenticity and legacy of Climate Positive commitments for host regions.