This review summarizes our studies of the past several years on the development of third generation dendritic cell (DC) vaccines. These developments have implemented two major innovations in DC preparation: first, young DCs are prepared within 3days and, second, the DCs are matured with the help of Toll-like receptor agonists, imbuing them with the capacity to produce bioactive IL-12 (p70). Based on phenotype, chemokine-directed migration, facility to process and present antigens, and stimulatory capacity to polarize Th1 responses in CD4(+) T cells, induce antigen-specific CD8(+) CTL and activate natural killer cells, these young mDCs display all the important properties needed for initiating good antitumor responses in a vaccine setting.