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We propose a framework for the understanding of the pathophysiology and management of Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS) that considers wider determinants of health and long-term temporal variation in pathophysiological features and disease phenotype throughout the natural history of the disease. As in other chronic diseases, ME/CFS evolves through different stages, from asymptomatic predisposition, progressing to a prodromal stage, and then to symptomatic disease. Disease incidence depends on genetic makeup and environment factors, the exposure to an insult, or repeated insults, and the nature of the host response. In people who develop ME/CFS, normal homeostatic processes in response to adverse insults may be replaced by aberrant responses leading to dysfunctional states. Thus, the predominantly neuro-immune and autonomic manifestations, underlined by a hyper-metabolic state, that characterise early disease, may be followed by various processes leading to multi-systemic related symptoms. This abnormal metabolic state and the effects of a range of mediators such as products of oxidative and nitrosamine stress, may lead to progressive cell and metabolic dysfunction culminating in a hypometabolic state with low energy production. These processes do not seem to happen uniformly; although a spiralling of progressive inter-related and self-sustaining abnormalities may ensue, reversion to states of milder abnormalities is possible if the host is able to restate responses to improve homeostatic equilibrium. Disease management and research efforts should seek to identify and apply strategies targeted at the different pathophysiological dysfunctions that characterise different disease stages. As disease presentation varies over time, no single case description, set of diagnostic criteria, or molecular feature is currently diagnostic for all patients at all times. While acknowledging its limitations due to the incomplete research evidence, we suggest the proposed framework may improve research design and health care interventions for people with ME/CFS.