AimsTo investigate for the first time the determinants and barriers of seeking help for mental disorders in the Arab world based on a national study: Lebanese Evaluation of the Burden of Ailments and Needs Of the Nation (L.E.B.A.N.O.N).MethodsA nationally representative (n = 2857) and multistage clustered area probability household sample of adults ≥18 years and older was assessed for lifetime and 12 months mental disorders using the Composite International Diagnostic Interview. In addition, detailed information was obtained on help- seeking behaviour and barriers to treatment.ResultsIn total, 19.7% of the Lebanese with mental disorders sought any type of treatment: 91% of those who sought treatment did so within the health sector. Severity and perceived severity of disorders predicted seeking help, the highest being for panic disorder. The greatest barrier to seek help was low perceived need for treatment (73.9%). Stigma was reported to be a factor only in 5.9% of those who thought about seeking treatment. Eighty per cent of the Lebanese reported they would not be embarrassed if friends knew they were seeking help from a professional.ConclusionsA small fraction of Lebanese seek help for their mental health problems: female gender, higher education and income are predictors of positive attitudes to help seeking. Severity and recognition of disorders, more than stigma, to get treatment seem to be the most important factors in determining help seeking. The findings underscore the importance of helping the public recognise mental health disorders.