Though Bangladesh is nearly open defecation free, nearly half of latrines are unimproved or have broken water seals, which are needed to prevent the spread of disease. Resulting health losses are over 4 billion dollars, 5% of GDP (WSP, 2012). Central to this problem is the limited availability of quality latrine components and a belief that latrines without seals are not a problem. The SanMarkS project aims to reach 450,000 people with improved sanitation facilities by strengthening the entire sanitation market system: changing beliefs to increase demand for quality latrines, engaging corporate firms and local entrepreneurs to increase supply of quality components, and enlisting regulatory or social welfare support from public and development sectors. This partnership between the Bangladesh Department of Public Health Engineering (DPHE), the Swiss Development Cooperation (SDC), Unicef, iDE, and Rangpur Foundry Ltd. (RFL), demonstrates how cross-sectoral partnerships can facilitate scalable, sustainable access to improved sanitation.