Nocturnal enuresis is a very common problem in childhood, various treatment have been suggested to cure bed-wetting, but the two most commonly used methods are the buzzer alarm and drugs. At Children's Hospital of Florence University, we dealt a trial to evaluate the effectiveness of conditioning treatment for nocturnal enuresis. We used a model alarm called "bell and pad". The child sleeps on a detector mechanism such as two separate metal mats that are connected with a buzzer alarm. When the voided urine wets the sheet, completing the electrical circuit, triggers the alarm and the child awakes. With repetition and unconscious inhibitory reflex is developed. 130 children were treated, 84 males and 46 females. Subjects were at least 6 years of age and not older than 15. 112 children had nocturnal primary enuresis and 18 secondary. The family history was positive in 70%. We had an initial interview with child and his parents. During this initial approach we explained the conditioning treatment. The child was given a diary card to record the bedwetting nights. We liked to see the child at three weekly intervals. After the child was dry for three consecutive weeks the metal mats was removed the bed. After a further three weeks of dryness the alarm was returned. Out of 130 cases there have been 109 cures (83%), whereas 21 (17%) haven't achieved dryness. There have been 14 relapses. Most children (77%) became dry within 12 weeks. The children with nocturnal secondary enuresis achieved later dryness. We believe that the use of enuresis alarm gives a high cure rate.(ABSTRACT TRUNCATED AT 250 WORDS)