Primary burning mouth syndrome (BMS) is a chronic, idiopathic intraoral mucosal pain condition that is not accompanied by clinical lesions or systemic disease. There is some uncertainty whether this condition should be referred to as a disease, a disorder, or a syndrome but there are insufficient data to justify any change in taxonomy at present. BMS occurs most often among women and is often accompanied by xerostomia and taste disturbances. More recently a neuropathological basis has been proposed so that BMS may be regarded as an oral dysesthesia or painful neuropathy. However, our incomplete understanding of the epidemiology, etiology, pathophysiology, and lack of diagnostic criteria are barriers to critical investigation and selection of effective treatments. There is only limited evidence to guide clinicians in the management of patients with BMS. Treatable secondary causes should be investigated before diagnosing primary BMS. Topical clonazepam and cognitive therapy have been proven efficacious in some patients. Emerging evidence supports the effectiveness of the antioxidant, alpha lipoic acid, with further studies of this agent being warranted. Additional research into mechanisms, diagnostic criteria, and randomized controlled interventional studies are needed.