You can’t fix housing without fixing mobility, and vice versa. This paper makes the case for planning homes, transport and urban growth as one connected system. It shows why affordability depends on more than rent, how location and transport shape emissions and access to opportunity, and why decisions made today can lock cities into costly, car-dependent patterns for decades. Drawing on examples from cities across different regions, it sets out 12 practical recommendations for integrated planning — from aligning housing and transport strategies to improving access, reforming parking rules and protecting residents from displacement. A timely resource for policymakers, urban planners and development partners working toward more affordable, inclusive and sustainable cities.