A new technique of multiplex quantitative tissue imaging has now allowed the mapping of dendritic cell (DC) subsets in steady-state lymph nodes. Histo-cytometry involves the use of fluorescence-conjugated antibodies, three-dimensional confocal microscopy and mathematical algorithms to quantitatively visualize various cell populations. Imaging of lymphocyte populations and antigen-induced T cell activation in the lymph nodes established histo-cytometry as a powerful method. So, the authors then used it to trace DC subsets in lymph nodes. Migratory CD11b+ DCs were found in the interfollicular zone, and resident CD8+ DCs, Langerhans cells and migratory CD103+ DCs localized in the T cell zone, whereas resident CD11b+ DCs were more predominant in the lymphatic zone. The compartmentalization of DCs reflects their recruitment by specific local cues and may determine the nature of presented antigens and co-stimulation, thereby influencing the type of T cell responses triggered by each DC subset.