The aim of this study was to survey current treatment practices for common infections in primary care as a basis for implementation of recently released evidence-based guidelines for community-acquired infections. A point-prevalence survey was conducted in 30 health centres in the Finnish primary care system with a population base of 819,777. All patients consulting the health centres for an infection during a 1-week period were included in the study. The main outcome measures were the prevalence of antibiotic prescription and the selection of drugs by infection diagnosis. Of the 7777 recorded consultations, 85% were with a physician and the rest with a nurse. The most common cause for a visit was respiratory tract infections (74%), followed by skin/wound infections and urinary tract infections (both 6%). The infection panorama varied markedly according to age: in the youngest children (< 5 y) 84% of the infections were respiratory tract infections whereas the corresponding figure for patients > 65 y was 50%; the proportions of visits for urinary tract infections in these age groups were 7% and 26%, respectively. Of the patients with acute bronchitis, 70% were treated with antimicrobial agents, mostly macrolides (39%) and doxycycline (36%). Of the otitis media patients, 53% were treated with amoxicillin, 16% with macrolides and 16% with sulphatrimethoprim. Macrolides were mostly used to treat otitis media (31%), acute bronchitis (26%) and sinusitis (20%). In conclusion, antimicrobial agents are still used excessively in Finland, particularly for the treatment of acute bronchitis. Moreover, the selection of drugs for treating sinusitis and otitis media is non-optimal; macrolides and cephalosporins are frequently chosen unnecessarily. Knowledge of the indication-based prescription practices for antimicrobial agents is essential in order to improve the treatment habits of primary care physicians. The data obtained in this study provide a unique tool for the active and targeted implementation of evidence-based guidelines for primary care physicians.