Standardized diagnostic criteria determined by the International Restless Legs Syndrome Study Group were used to investigate the current prevalence of restless legs syndrome (RLS). Possible associations between RLS and neuropsychiatric and somatic complaints were also investigated. A random sample of 4,000 men living in central Sweden were sent a questionnaire that included questions about sleep habits, symptoms of sleepiness, and somatic and neuropsychiatric complaints. Four symptom questions accepted as minimal diagnostic criteria for RLS were also included. Odds (OR) ratios and 95% confidence interval (CI) for different variables were calculated by means of multivariate logistic regression; 5.8% of the men suffered from RLS. The prevalence of RLS increased with age. Sleep-related complaints were more frequent among the RLS sufferers. Complaints of headache at awakening and daytime headache were reported three to five times more frequently among RLS sufferers and there was a tendency toward reported social isolation related to RLS. Subjects with RLS more frequently reported depressed mood (OR, 2.6; 95% CI, 1.8-3.8), and complained more often of reduced libido (OR, 2.2; 95% CI, 1.4-3.3). RLS sufferers more frequently reported hypertension (OR, 1.5; 95% CI, 0.9-2.4) and heart problems (OR, 2.5; 95% CI, 1.4-4.3). Results show that restless legs syndrome is common among men. It is hypothesized that RLS may be associated with several somatic and neuropsychiatric symptoms. Copyright 2001 Movement Disorder Society.