The Boston region has one of the most successful bike share programs in America. Four years after its launch, the system (then called Hubway) faced new challenges, such as looming increases in maintenance costs, the need to better serve low-income communities in Boston, and impending end of its existing operating contract and title sponsorship. Foursquare ITP aided the City of Boston in navigating these challenges and developing a sustainable vision for the future. Our team conducted a detailed market analysis to determine locations of greatest ridership demand and areas where public policy and equity indicate bike share need. We tested expansion scenarios using a dynamic ridership and revenue model that Foursquare ITP customized for Hubway’s demand characteristics and financial structure. The final constrained plan informed the system expansion and future vendor procurement and sponsorship contracts.