The diagnosis of chronic Lyme disease has been embroiled in controversy for many years. This is exacerbated by the lack of a clinical or microbiologic definition, and the commonality of chronic symptoms in the general population. An accumulating body of evidence suggests that Lyme disease is the appropriate diagnosis for only a minority of patients in whom it is suspected. In prospective studies of Lyme disease, very few patients go on to have a chronic syndrome dominated by subjective complaints. There is no systematic evidence that Borrelia burgdorferi, the etiology of Lyme disease, can be identified in patients with chronic symptoms following treated Lyme disease. Multiple prospective trials have revealed that prolonged courses of antibiotics neither prevent nor alleviate such post-Lyme syndromes. Extended courses of intravenous antibiotics have resulted in severe adverse events, which in light of their lack of efficacy, make them contraindicated.