This article is a PDF document created by WHO in collaboration with the UN. It begins by giving a broad definition of sanitation and its many components before explaining why it is an important issue and how many are effected by inadequate sanitation. The article also covers various diseases that can be caused or worsened by poor sanitation, particularly parasitic infections, as well as costs on both an economic and environmental scale. Potential solutions, including off-site and on-site disposal methods and wastewater treatments, are briefly covered, followed by current obstacles in implementing said structures and raising awareness about sanitation.
One important note about this article is that it is a bit outdated in terms of statistics, although most of the information and the general knowledge remains relevant. The latest year that the article gives data for is 2004.