This review focus on the epidemiology, diagnosis and treatment of prolactinomas. In particular, attention was given to recent data showing a high prevalence of these tumours in the general population, 3-5 times higher than previously reported. The diagnosis of hyperprolactinaemia has been simplified in recent years, and only prolactin (PRL) assay and magnetic resonance imaging of the sella are required. Nonetheless, macroprolactinaemia should be assessed in patients with hyperprolactinaemia in the absence of clinical symptoms of elevated PRL levels. The recent evidence that medical therapy with dopamine agonists should be continued lifelong has been confirmed by several studied. The patients achieving disappearance of the tumours and suppression of PRL levels during treatment are those showing the highest likelihood to have persistent remission of hyperprolactinaemia after treatment withdrawal.