70% of its emissions come from buildings, so NYC cannot meet their 2050 carbon neutrality commitments unless they aggressively decarbonize 50,000 of their largest properties. To accomplish this, NYC passed the 2019 Climate Mobilization Act, a series of building policies, most notably Local Law 97 (LL97), which assigns increasingly stringent emissions limits on large buildings, beginning in 2024. NYC was one of the first and the largest cities to pass such policy. Approximately 75% of the properties could face fines by the end of the decade causing the need for accelerated decarbonization. The implementation of aggressive pollution-cutting building policies is not enough. NYC understands a massive market disruption requires direct market support and behavioral change programming through the NYC Accelerator. The program not only helps NYC building owners understand the new policies but also provides direct support to help reduce emissions and avoid future impacts of LL97. NYC Accelerator targets existing large and affordable buildings, and new and existing high-performance buildings with a unique concierge service providing personalized guidance on clean energy, building laws, incentives, and financing to fund upgrades. The short-term goal of the Accelerator is to reduce consumption and comply with LL97 while long-term is to animate and move the market toward a net zero future. To drive transformation, the market had to be informed and mobilized so marketing and direct outreach was key to driving awareness and action. Since 2021, the NYC Accelerator has supported over 5,000 large buildings with decarbonization projects and LL97 compliance and 5,000 more are in process. The proposed panel presentation will discuss specific tactics employed to drive mass mobilization from separate perspectives. Jessica Horne and Luke Surowiec of NYC Accelerator will cover the policy, effective marketing, and direct outreach efforts.