In this review we have summarized the main data concerning Leishmania-macrophage interactions, with particular emphasis on receptors involved in adhesion, activating or deactivating cytokines and toxic molecules responsible for parasite killing. At present it is also known that a different T helper (Th)1- or Th2-cell response may be critical for the outcome of Leishmania infection in human and in murine models. Therefore, we have mentioned the recent studies on cytokines, such as IL-2, which are able to cause the switch from a Th2, disease-promoting immune response, to a Th1, protective response. In fact, in the light of these findings, these molecules may be used in the future for immunotherapeutical or immunoprophylactic purposes.