Mammalian Toll-like receptors (TLRs) were first identified in 1997 based on their homology with Drosophila Toll, which mediates innate immunity in the fly. In recent years, the number of studies describing TLR expression and function in the nervous system has been increasing steadily and expanding beyond their traditional roles in infectious diseases to neurodegenerative disorders and injury. Interest in the field serves as the impetus for this volume in the Current Topics in Microbiology and Immunology series entitled 'Toll-like receptors: Roles in Infection and Neuropathology'. The first five chapters highlight more traditional roles for TLRs in infectious diseases of the CNS. The second half of the volume discusses recently emerging roles for TLRs in non-infectious neurodegenerative diseases and the challenges faced in these models with identifying endogenous ligands. Several conceptual theories are introduced in various chapters that deal with the dual nature of TLR engagement and whether these signals favor neuroprotective versus neurodegenerative outcomes. This volume should be informative for both experts as well as newcomers to the field of TLRs in the nervous system based on its coverage of basic TLR biology as well as specialization to discuss specific diseases of the nervous system where TLR function has been implicated. A must read for researchers interested in the dual role of these receptors in neuroinfection and neurodegeneration.