The Disease Reference Group on Chagas Disease Human AfricanTrypanosomiasis and Leishmaniasis (DRG3) was part of an independent thinktankof international experts established by the Special Programme for Researchand Training in Tropical Diseases (TDR) to identify key research prioritiesthrough systematic review of research evidence and input from stakeholders.These three distinct insect-borne diseases while caused by related kinetoplastidprotozoan pathogens have dissimilar geographical distributions a reflection oftheir different insect vectors and range of vector contact with humans. Thediseases disproportionately afflict poor and remote populations with limitedaccess to health services; the pathogenic mechanisms are poorly understood buttypically entail immunological processes.