Cytokines are involved early in the pathogenesis of HIV infection and disease progression as a component of immunologic dysregulation and immunodeficiency and as determinants controlling virus replication. Several steps, before and after retroviral integration into host DNA in T cells and macrophages, are affected by cytokines whereas CCR5 and CXCR4 binding chemokines can interfere with viral entry. A growing number of potential players--including the gamma-common interleukin (IL)-7, IL-15, and IL-21 together with IL-17, IL-18, IL-19, IL-20, IL-23, and IL-27--are discussed in terms of their perturbation in HIV infection and of their effects on virus replication. Thus, an increasing intersection of HIV infection and the cytokine network represents a crucial determinant of virus replication and immunologic dysregulation and will likely play a key role in the development of effective strategies of HIV prevention and immunologic reconstitution.