Leishmania braziliensis is the most prevalent species causing tegumentary leishmaniasis in Brazil. Corte de Pedra, a district in Bahia state, Northeastern Brazil, is an area of L. braziliensis transmission, with average of 1,000 cases of tegumentary leishmaniasis diagnosed per year. Cutaneous leishmaniasis (CL) is the most prevalent clinical form of the disease, occurring in 90% of the cases. Mucosal (ML) is diagnosed in 3% of the cases concomitantly or after CL. Disseminated leishmaniasis (DL), characterized by more than 10 up to more than 1,000 papular, acneiform and ulcerated lesions, is an emerging form of the infection with a 30-fold increase of prevalence in the last 25 years. About 1% of the patients present atypical lesions as verrucous, multiple nodular lesions in one area of the body, or large ulcers with non- limited borders. Moreover, about 20% of subjects living in this area, and without previous history of CL, have a subclinical infection. It is not clear what is the wild reservoir of L. braziliensis, but about 20% of the dogs have evidence of L. braziliensis infection detected by PCR in skin biopsies, and the ratio for infections/disease in dogs is 7:1. Canine tegumentary leishmaniasis is characterized by un ulcer similar to the one observed in humans with CL. L. braziliensis and L. amazonensis where the two species causing tegumentary leishmaniasis in the past, however for more than 20 years L. braziliensis has been the only species detected in this area. L. braziliensis is polymorphic in this region and genotypic differences among parasites of the same species is associated with the different clinical forms, severity of the disease and high rate of failure to therapy. Over a 20 years-period, there was an increase in tegumentary leishmaniasis in children and in individuals with more than 60 years of age, suggesting peridomiciliary and domiciliary transmission. CL, ML and DL patients share the same immunopathogenesis features, characterized by an exaggerated inflammatory response and low number of parasites. High levels of proinflammatory cytokines, TNF, IFN- , IL-17, IL-1 and IL-6 participate of the pathology, but cytotoxicity mediated by NK and CD8+ T cells have been considered the most important immunological responses associated with tissue damage in L. braziliensis infection. Although significant differences in immune response may not be linked to the occurrence of the different clinical forms, high levels of IL-1 and high parasite burden is associated with longer time to heal and therapeutic failure to pentavalent antimon.