A group of enzootic and zoonotic protozoan infections, the leishmaniases constitute among the most severely neglected tropical diseases (NTDs) and are found in all continents except Oceania. Representing the most common infectious diseases, NTDs comprise an open-ended list of some 20 parasitic, bacterial, viral, protozoan and helminthic infections. Called “diseases of the poor,” because of their characteristic prevalence in poor populations regardless of a country's income status, they infect over one billion people in over 140 countries, with about 90% of the global burden in Africa. While NTDs do not contribute significantly to global deaths, they are debilitating and remain the most common infections among the poor worldwide, preventing them from escaping poverty by impacting livelihoods such as agriculture and livestock, and affecting cognitive, developmental and education outcomes.