Three commercially available test systems for the identification of nonfermentative gram-negative rods were compared: API 20NE, flow N/F and Minitek Nonfermenter System. Two hundred strains were identified by conventional means and by each test system. The rate of correct identification of Acinetobacter, Alcaligenes, Flavobacterium and Moraxella strains to genus level and of the other genera to species level was 92% with API 20NE, 84% with flow N/F and 75% with Minitek Nonfermenter System. The need for these kits in the diagnostic hospital laboratory is also discussed.