Until the mid-1990s, Mexican cement company Cemex mostly sold building materials to big contractors. When an economic crisis decimated sales, it overhauled that business model—finding a new market in Mexico’s urban working class. In exchange for fixed, regular payments, Cemex began sending building materials and technical support to do-it-yourselfers, enabling many to own their own homes for the first time. Today nearly a half-million families across Latin America have built Cemex-supplied homes at one-third the time and cost.