The Self-Employed Women's Association (SEWA) of India, owned and managed by poor women in the informal sector,has been offering housing and infrastructure loans sustainably since the 1970s. This article describes how SEWA and its bank was formed and argues that housing loans can boost self-employed women's productivity. It outlines how the interest rate is set and how repayments are made regularly by door-to-door collectors. SEWA Bank has remained in profit since the 1980s. An important additional component is technical assistance to advise women on building techniques and on how to organize to secure infrastructure.