Across North America, obsolete infrastructures are being reimagined as platforms for public life in the twenty-first century. Celebrated for their design ambition and catalytic potential, these projects promise to reconnect neighborhoods and transform landscapes--but also risk intensifying uneven development and displacement. Community First, By Design reveals why infrastructure reuse projects so often encounter similar equity challenges, regardless of location or intent. Organized around five recurring typologies--rail and linear corridors, waterfronts, highways and bridges, cultural networks, and legacy park systems--the book links physical form to inherited histories, development pressures, and institutional leverage, offering practical pathways forward. Drawing on nearly 40 reuse projects, Stephen Francis Gray shows how decisions about sequencing, land control, partnership structure, and governance shape outcomes as decisively as design itself--often long before projects become publicly visible. At its core is the award-winning Community First Toolkit: 18 actionable tools, collaboratively developed by Harvard and the Urban Institute for the High Line Network, that help practitioners clarify purpose, align internal systems, structure partnerships, and embed accountability while leverage still exists. Neither manifesto nor mitigation strategy, this book positions equity as a design discipline--exercised through deliberate, cumulative decisions that shape how cities evolve.