Although understudied, CD8 + T cells appear to play an important role in the immune response to most Leishmania infections. Pilot studies in the murine model of VL have also demonstrated that adoptive transfer of antigen-specific CD8 + T cells (Polley et al., 2006) or reactivation of CD8 + T cell responses through a therapeutic vaccine (Joshi et al., 2009) results in the control of parasite growth. A better understanding of the mode of activation, the specificity, and effector functions of the various CD8 + T cell subsets generated during Leishmania infections could ameliorate the design of vaccines and of novel therapeutic interventions.