Aim: To investigate appropriateness of referral of the hypertensive patient to hypertension Specialist according to guidelines. Methods: We have examined data of 9874 hypertensive Caucasian patients consecutively referred to an hypertension clinic between 1989 and 2008. For each patient we have considered the first visit data as indicators of the patient's management by practitioners. Appropriateness was identified by almost one of these indicators: blood pressure values and its control, suspected or confirmed secondary and pediatric hypertension, blood pressure >180/110 mmHg, resistant hypertension (blood pressure >140/90 mmHg with three drugs) and co-morbidities or severe target organ damage at the time of first visit. Analysis was divided in three periods (1985–1994, 1995–2001, 2002–2008) to study the variability in the patient's data and to analyse the practitioner's conduct according to different guidelines. Results: Only 59,3% of patients were correctly referred to Hypertension Unit, considering secondary forms of hypertension (6,3%) pediatric hypertension (1%), blood pressure >180/110 mmHg (22,5%), resistant hypertension (15%), and hypertension with target organ damage or co-morbidities (40%). The value of corrected reference to our Unit changes from 65,5% in the first period, to 70,5% in the second and 47,4% in the third. Mean blood pressure values at entry were 155/94 mmHg, with a tendency, into three periods, to blood pressure reduction (from 161/99 mmHg in the first period, to 150/90 mmHg in the third one). The 16% of patient at entry have blood pressure values less than 140/90 mmHg, with a significant increased percentage in the three periods (5,8% and 23,4% respectively in the first and last period). Conclusion: Since more than a third of referrals to Hypertension Unit can be defined as inappropriate, thus further investigation is needed to identify all underlying factors responsible or methods available (such as medical education, feedback from consultants or guidelines for referral) to reduce this inefficient process.