Potential causal factors have been extensively studied and reviewed, suggesting a multifactorial aetiology, that apparently includes local, systemic and psychogenic factors. However, reports of their relative importance are conflicting. Consequently this lack of evidence is reflected in inconsistent guidelines for diagnosis and treatment. Most of the authors emphasize the importance of history taking and clinical intraoral examination for diagnosis. The symptom of burning mouth associated with clinical mucosal abnormality has to be differentiated from burning mouth syndrome (BMS), a condition in which no mucosal abnormality is evident on examination. Whereas the symptom of burning mouth associated with clinical mucosal signs is described to be often manageable by eliminating possible causal factors, the background of most of the proposed treatments for BMS is empiric or even purely anecdotal. Only a few randomised controlled studies have been performed on treatment outcome. Their differing results are presented in a short overview.