This review describes the worldwide situation of visceral and tegumentary leishmaniasis with an emphasis on diagnosis, including methods for the detection of antibodies, antigens, parasite DNA and of skin testing. The advantages and problems of each method are discussed and the need for a rapid, sensitive and low-cost diagnostic method for use in field conditions is highlighted. Recent advances in Leishmania genome sequencing, the use of DNA microarrays and protein microarray methodologies and their potential use for leishmaniasis diagnosis are presented.