Neuroinflammation, the response of the central nervous system (CNS) to disturbed homeostasis, typifies all neurological diseases, from primary-inflammatory; to developmental; traumatic; ischemic; neoplastic; and neurodegenerative. Disease-associated neuroinflammatory responses aren’t evolutionarily-selected to minimize or repair tissue injury, and may be helpful, harmful or neutral. This research is promising because neuropathological, epidemiologic, genetic, animal-model and biomarker studies indicate pertinence of inflammation for neurological disease and because current and re-purposed therapeutics might beneficially modify neuroinflammation. The research is urgent because therapeutic options for these diseases are presently lacking. The meeting will: 1) Address the developmental roles of neuroinflammatory cells including microglia and blood-brain barrier (BBB) neurovascular elements; 2) Clarify how neuroinflammatory reactions mediate host defense against neuroinvasive microbial pathogens and also how the response to systemic inflammation affects the neuroinflammatory elements.; 3) Specify critically-important neuroinflammatory cells (microglia; astrocytes; NG2+ glia; BBB); receptors (Toll-like receptors; inflammasomes; cytokine receptors); signaling pathways and effector mechanisms; and 4) Identify the most salient targets of neuroinflammation (neurons; neural progenitor and stem cells; oligodendroglia) and mechanisms of injury. Neuroscientists and immunologists work on individual elements of these questions. This meeting will develop a common body of knowledge and opportunities for productive interaction, to begin maturing the field. This meeting will be the first Keystone Symposia meeting on neuroinflammation. Single-disease-focused meetings have occurred and suggest opportunities of neuroscientist/immunologist interactions. The present meeting will be the first to bring together the many communities of disease-focused neuroscientists and immunologists with an interest in the CNS. This nascent field needs a committed, interactive community and this Keystone Symposia conference promises to play a key role.