Interferons (IFNs) are receiving increasing attention by dermatologists for both therapeutic applications,1 as well as for investigations of their role as potential mediators of inflammation and cellular proliferation (an International Dermatology Symposium on "Interferons and Related Lymphokines" is planned for October 1989 in Berlin). As Shiohara et al in this issue of the Archives indicate, IFNs may be important in psoriasis.2 In a previous editorial I reviewed this topic and concluded that due to the multiplicity of biologic effects of IFNs, more basic scientific knowledge was required to determine the role(s) of IFNs in skin diseases.3 One of the major new developments that was previously alluded to involves the ability of IFN-γ to modulate T lymphocyte trafficking in the skin.3 This editorial focuses primarily on the role of INF-γ in modulating the accumulation of peripheral blood monocytes and lymphocytes (PBML) in the skin, and is divided