To learn about the sustainability of rural sanitation in Bangladesh, the Water and Sanitation Program (WSP) in conjunction with the Government of Bangladesh and NGOs felt it was important to investigate several knowledge gaps: the degree to which sanitation behaviors and facilities are being sustained in Union Parishads declared ODF at least four and a half years ago;  the level to which sanitation programming has been sustained in these Union Parishads, and to the degree possible, whether this programming is contributing to sustained behaviors;  if there are perceived benefits associated with maintaining ODF status and if these benefits are contributing to sustained latrine use;   the degree to which private sector sanitation service providers have been sustained, and whether household access to them contributes to sustained latrine use; and identifying other factors that may work in favor of or against sustained sanitation behaviors and facilities.