Sjögren's syndrome (SS) is an autoimmune disease leading to mucosal dryness. It may also involve joints, nerves, kidneys and lungs. Patients with SS are also at increased risk for lymphoma. Diagnosis of SS relies on clinical, biological, histological and radiological criteria, after exclusion of other causes. Initial work-up may be performed in general practice, by serology (antinuclear and anti-SSA/SSB antibodies, rheumatoid factor) and by measuring lacrimal and salivary flow. Antibodies may be within normal range in up to one third of patients and when present are not specific for SS. Histological proof of lymphocytic sialadenitis is precious but invasive. Major salivary glands sonography may help select candidates for labial biopsy. This article elaborates the steps to be taken in case of suspected SS, in order to facilitate early diagnosis.