BACKGROUND. Although non-diphtherial corynebacteria are ubiquitous in nature and commonly colonise the skin and mucous membranes of humans, they rarely account for clinical infection. METHODS AND RESULTS. 10 patients with unilateral conjunctivitis are described in whichCorynebacterium macginleyi was isolated. This species has only recently been reported to be exclusively isolated form ocular surfaces. C macginleyi was uniformly susceptible to topical antibiotics commonly used in ophthalmology. CONCLUSION. Despite the fact that the pathogenicity of C macginleyiis not yet assured, this micro-organism should be recognised as a potential cause of bacterial superinfections. Appropriate antibiotic therapy leads to its elimination and resolution of the conjunctivitis.