In a pilot study we established a hospital antibiotic use database from which estimates for antibiotic consumption in German hospitals (expressed as defined daily doses per 100 patient days, DDD/100) can be retrieved for both benchmarking and antibiotic use and resistance research purposes. Data from eight university hospitals (1998-2000) showed a mean antibiotic use density of 60.1 DDD/100 in the surgical and 79.3 DDD/100 in the medical services. Antibiotic use was higher in the intensive care units (surgery: 146 DDD/100, medicine: 187 DDD/100) than in haematology-oncology services (110.8 DDD/100) or in other surgical (51.6 DDD/100) and medical (66 DDD/100) service areas. There were major differences in the use of specific antibacterial drug classes between service areas. The established database allows detailed analysis in antibacterial drug use and can be linked to bacterial resistance surveillance databases.