Data about the prevalence of rosacea are scarce. The aim of this study was to evaluate the prevalence rate of rosacea according to the American National Rosacea Society Expert Committee (NRSEC) classification. A cross-sectional study of 348 subjects randomly selected from a working population >or= 30 years of age was performed. All subjects completed a questionnaire. Skin status was examined according to NRSEC criteria. Of the 348 subjects, 78 (22%) had one or more primary features of rosacea. The most common features were erythema (21%) and telangiectasia (18%). Of the subjects with rosacea, 78% had erythematotelangiectatic rosacea and 22% had papulopustular rosacea. Fifteen percent of the study subjects had experienced frequent episodes of flushing without permanent features of rosacea. No significant gender-related differences were found between study groups. In conclusion, according to the NRSEC, rosacea is a more common skin condition over the age of 30 years than previously thought.