World Toilet Day (WTD) is an official United Nations international observance day on 19 November to inspire action to tackle the global sanitation crisis. Worldwide, 4.2 billion people live without "safely managed sanitation" and around 673 million people practice open defecation. Sustainable Development Goal 6 aims to "Ensure availability and sustainable management of water and sanitation for all". In particular, target 6.2 is to "End open defecation and provide access to sanitation and hygiene". When the Sustainable Development Goals Report 2020 was published, United Nations Secretary-General António Guterres said, "Today, Sustainable Development Goal 6 is badly off track" and it "is hindering progress on the 2030 Agenda, the realization of human rights and the achievement of peace and security around the world".

Sanitation refers to public health conditions related to clean drinking water and treatment and disposal of human excreta and sewage. Preventing human contact with feces is part of sanitation, as is hand washing with soap. Sanitation systems aim to protect human health by providing a clean environment that will stop the transmission of disease, especially through the fecal–oral route. For example, diarrhea, a main cause of malnutrition and stunted growth in children, can be reduced through adequate sanitation. There are many other diseases which are easily transmitted in communities that have low levels of sanitation, such as ascariasis, cholera, hepatitis, polio, schistosomiasis, and trachoma, to name just a few.