The focus here is largely on the period of the Millennium Development Goals (The UN MDGs were replaced by the Sustainable Development Goals in 2015). However, there is also some brief discussion given to the more contemporary situation of sanitation workers later in this chapter, as it is a perhaps somewhat overlooked but important part of the sanitation picture regarding both health and quality-of-life outcomes. The overarching theme of this chapter is that great progress has been made in sanitation delivery, but challenges remain.