To better define the spectrum and relative incidence of pathogens causing dacryocystitis in adults, samples of purulent lacrimal sac contents were obtained from 236 patients undergoing dacryocystorhinostomy for a clinical diagnosis of dacryocystitis. Positive culture results were obtained in 52.5%. Cultures were pure, consisting of a single organism in 71%, and were mixed in 29%. Gram-positive organisms were most common, accounting for 64.5% of the isolates. Staphylococcus epidermidis, comprising 27.3% of the isolates and Staphylococcus aureus, comprising 22.1% of the isolates, were the most frequently encountered organisms. Gram-negative organisms were present in 27.3% of the isolates with Pseudomonas aeruginosa the most common, accounting for 8.7% overall. Anaerobic organisms were found in 7.0% of the isolates with Propionibacterium acnes the most frequent, recovered in 4.7% overall. Unexpected findings included the paucity of Streptococcus pneumoniae organisms recovered and the high incidence of involvement by gram-negative and anaerobic organisms.