Sleep talking is very common in the general population. Its prevalence remains stable from childhood through adulthood. Sleep talking is often associated with other parasomnias: sleep walking, sleep terrors or REM sleep behavior disorders. It may arise from either REM or non REM sleep, when associated with REM sleep it is more comprehensible and often associated with clear sentences and recall of sleep mentation. Sleep talking is a benign entity and does not require any treatment; however an exceptional organic cause or psychopathology should be suspected if the onset is late (after 25 years); if the mental content is too violent or too emotional.