Nonfermentative Gram-negative bacilli were commonly isolated from clinical material in a Malaysian hospital over a two year period of study. Pseudomonas aeruginosa, Acinetobacter sp and other Pseudomonas were the most common organisms seen. Although these bacteria occurred regularly in clinical specimens their pathogenetic role could be established in only a small proportion of cases. Most 01 these organism were either contaminants or
commensals 01 the normal bacterial flora. It is important to interpret the isolation of a nonfermentative Gram-negative bacillus with caution, and in the light of clinical findings. Failure to do so may result in the unnecessary use of antibiotics.