Thirty-one isolates of Acinetobacter baumannii were collected from ten intensive care units of an Austrian university hospital. All isolates were typed by enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR). Two strains colonizing 13 infants in the neonatal intensive care unit were identified by ERIC-PCR. All other Acinetobacter baumannii isolates had highly divergent ERIC-PCR patterns, despite having the same antibiogram. Thus, a hospital-wide clonal distribution, as suggested by identical antibiogram patterns, was excluded by ERIC-PCR.