The aim of the study was to estimate the occurrence of mood, anxiety and disability disorders in 300 patients affected by chronic daily headache and MOH, who were observed for a 16-month period in our centre. We monitored the patients on an interview basis, concerning the anamnestic data collection related to the pre-morbid period, information given by relatives regarding the patient's behaviour during the day, attitudes towards others, maintenance of previous interests and enjoyments, and modifications of the biological rhythm. Several tests were conducted, underlining a significant correlation between headache and mood disorders, impairment of working activity, social and family life. The study shows that patients affected by chronic daily headache and MOH present high levels of anxiety, a depressive symptomatology associated with alexithymia. Moreover, it has been discovered that anxiety and depression facilitate the onset of headache, while patients suffering from pain persistence were more vulnerable to psychiatric problems. In consideration of these results, more exhaustive evaluations relating to the psychopathological aspects in patients affected by headache are necessary.