During the period from 1998 through 2004, a total of 476 isolates of Acinetobacter calcoaceticus-baumannii complex were recovered. The organism showed high rates of resistance to ampicillin (86% of isolates), cefoxitin (89%), and nitrofurantoin (89%). The rate of resistance to imipenem was 3%; to ticarcillin-clavulanic acid, 16.5%; to gentamicin, 26%; and to ceftazidime, 38%. Multidrug resistance was observed in 14%-35.8% of Acinetobacter species isolates.