The diagnosis of visceral leishmaniasis is difficult. Due to the limitations of direct methods to detect parasites, indirect immunological methods are widely employed. The simple affordable and sensitive/specific direct agglutination test (DAT) is perhaps the most important diagnostic tool under field conditions. A significant improvement of this test is the use of a freeze-dried antigen, which is heat-stable and has a long shelf-live even under harsh conditions. The performance of this antigen in DAT has been evaluated using samples collected in East Africa. The results of these studies are presented. The detection of Leishmania infection in HIV-co-infected patients is difficult. The combination of DAT-PCR may be useful for the detection of parasite infection in these patients. Finally, we present data to show that the DAT based on the freeze-dried antigen can also be used for the detection of anti-Leishmania antibodies in dogs.