Rapid Urbanism's mission is the promotion of politically viable, administratively manageable and financially affordable tools that, collectively, empower societies to tackle rapid urbanization challenges at speed and at scale. This way, Rapid Urbanism seeks to create responses that are meaningful—given the magnitude and velocity of urbanization, constrained capacities and shortage of resources. Rapid Urbanism collaborates with public policy makers, urban professionals, community activists and citizens in rapidly urbanizing cities. Rapid Urbanism connects private and public resources to self-managed organizations of the urban poor. Appreciating informality and its contribution to society, we learn from informal systems that arise as creative responses to policy failures. Then we use our gained knowledge to design curative and preventive policies that use truly inclusive interfaces between formal and non-formal systems. Rather than forcing their formalization, bottom-up processes serve as multipliers for top-down interventions to produce an incrementally improving, sustainable and resilient habitat with social networks, access to financial services, land, shelter, basic infrastructure and life-affirming employment opportunities for all. At present we are developing our Rapid Urbanism Pattern language: a toolbox with spatial planning, social organization, economic development and regulatory instruments that synergistically complement each other.