When a beloved teacher is tragically killed in a hit-and-run accident in Greenpoint, Brooklyn, a grassroots movement emerges to transform a notoriously dangerous four-lane boulevard into a safer, two-lane street with protected bike lanes. While many applaud the proposed change, it also sparks a backlash – led in part by a powerful local business owner. As government support begins to waver, neighbors unite to challenge entrenched interests and fight for a safer Greenpoint. Changing Lanes situates this local struggle within broader historical, environmental, political, and social contexts through interviews with politicians, activists, urban planners, entrepreneurs, and cultural icons including David