OBJECTIVE: Early identification of Harmful Drinking (HD) is difficult, and underestimated. The aim of our retrospective study was to investigate the presence of HD in a population of subjects who had their driving license suspended due to driving under the influence of alcohol. MATERIALS AND METHODS: We retrospectively recruited 979 subjects. During the first appointment (T0), clinical and laboratory characteristics of patients were evaluated, and the AUDIT questionnaire was administered. Two groups were then defined: Harmful Drinking (HD) and non-HD, and all subjects underwent a brief interview for 5-10 minutes before being assigned to a group. RESULTS: 95.9% of our sample were identified as non-HD, whereas 4.1% of them were HD; twenty-one (2.1%) of the HD underwent a control appointment (T1), and 17 (1.7%) of them were diagnosed with alcohol use disorder (AUD); there was a statistically significant reduction in mean daily alcohol intake (p<0.009), and in the mean values of the blood markers of HD between T0 and T1 in HD. CONCLUSIONS: The present study shows that 4.1%, and 1.7% of subjects presented a diagnosis of HD and AUD, respectively, and their entry in a protocol of drinking monitoring proved beneficial in reducing alcohol intake. Thus, the implementation of strict surveillance of subjects found driving under the influence of alcohol involving a network of professional figures (from police forces to specialists in alcohol addiction treatment) may help to detect and to treat subjects with HD and AUD, and to monitor their alcohol use over time