BACKGROUND AND OBJECTIVE: Dengue is the most common imported arbovirus infection in Europe. International travel and an increasing incidence of dengue fever in tropical areas have defined the disease as an emerging infection in returning travellers. We describe the clinical and microbiological features of imported dengue in 3 referral hospitals in Spain. PATIENTS AND METHOD: We included patients diagnosed with dengue infection during a 3-year period (2002-2005). We recorded clinical and epidemiological data and collected blood samples for serological and molecular studies of dengue infection. Data was analyzed with the statistical package Stata 9.2. RESULTS: We diagnosed 61 dengue cases, mostly European tourists who travelled to Latin America. Fever was found in 98.4% of patients and 80.3% presented with cutaneous eruption. Five patients had severe symptoms. Eighteen percent were considered to have secondary infections, although no patients met the WHO criteria for hemorrhagic dengue. In 26 cases, dengue was confirmed through viral genome detection and 35 cases through serology. Four patients were considered as «probable» dengue infection, and 57 as «confirmed». CONCLUSIONS: Dengue is a common diagnosis for returning travellers, and it may present with severe manifestations. In our sample, there was an elevated percentage of secondary infections even though no previous history of dengue was reported by the patients. Hemorrhagic dengue and septic shock dengue are a risk for travellers returning from endemic areas.