The treatment of oral lichen planus (OLP) remains a real challenge for clinicians who deal with this patient population and thus with diagnosis of this disease. Most treatment failures are attributable to improper diagnosis. Therefore, before a patient is started on therapy, a biopsy must be done and the diagnosis established. Most patients with OLP are asymptomatic, and once the diagnosis is established, patients need to be seen once a year to monitor their disease. However, when OLP is symptomatic, it can interfere with the patient's everyday life, making it difficult to work and to eat. The most symptomatic forms of the disease are the erosive and atrophic types. Often, systemic therapy is the only way to control the acute presentation of the disease. The most effective treatment modality to control the signs and symptoms of the disease is short courses of systemic steroids (prednisone) and topical high-potency corticosteroids. Other forms of therapy include the use of cyclosporine (topical) and retinoids, both systemic (etretinate) and topical (tretinoin). However, there is no one single standard protocol proven effective with either systemic retinoids or topical cyclosporine. Results so far are controversial and not very encouraging. One aspect clinicians must remember when designing treatment protocols for erosive OLP is the chronic course of the disease and its recalcitrant nature. These factors mean that treatment has to be long, and the onset of adverse side effects from long-term therapy must be taken into account. Alternate-day treatment protocols, low doses, and adjunct therapy all should be considered when a new agent is being considered for treating erosive OLP.