Neuroinflammation comprises the interaction of two formidably complex organ systems. Two considerations motivate this meeting: first that the communities of neuroscientists and immunologists urgently need to formulate and deploy a joint set of concepts to promote mechanistic progress (hence a meeting of the two), and second that neuroinflammation, broadly conceived, operates throughout life from embryogenesis through old age with consequences bearing on the most serious health concerns ranging from autism and schizophrenia to dementia. What’s needed in this field (for example) is for immunologists to acquire a working knowledge of neuroscience (e.g., electrophysiology, neurotransmitters, behavior) and for neuroscientists to become comfortable with the cells, proteins and animating concepts of contemporary immunology. The optimal venue for such exchange lies in the presentation of compelling multidisciplinary research to a joint audience in the Keystone Symposia format. As such, this meeting aims to: 1) Integrate the intrinsic “immune” elements of the CNS (microglia, complement, certain chemokines) into a broader scheme of neurodevelopment and to indicate where aberrant function of these elements might conduce to neurodevelopmental disorders such as autism; 2) Characterize the neuroinflammatory processes which typify aging and integrate this temporal dynamic into the pathogenesis of neurodegenerative disease; and 3) Share model systems (particularly invertebrate) and technical innovations which can be particularly powerful for generating mechanistic insights into neuroinflammatory processes.