Acinetobacter species are non-fermentative Gram-negative coccobacilli that are ubiquitous in the environment. The archetype pathogen within the genus is Acinetobacter baumannii, however, other species have the potential to cause human infection, especially in the hospital setting. We describe a patient with infection due to Acinetobacter radioresistens, a rare agent of human disease, which is often misidentified using biochemical methods. Acinetobacter radioresistens is the source of the Class D OXA-23 carbapenemase that can confer carbapenem resistance in A. baumannii. Therefore, accurate identification of A. radioresistens is important for clinical management and to potentially prevent the spread of carbapenem resistance.