1. The records of 166 compound fractures occurring in the long bones have been studied.
2. All of these fractures were treated by primary suture, following débridement and irrigation. Forty-two of the total number had one of the sulfonamides applied locally in the wound, and thirty of these received systemic treatment in addition.
3. Definite infection occurred in 19.3 per cent. of the wounds treated without the drug. Infection developed in 19.0 per cent. of the wounds in which the sulfonamide drug was implanted.
4. We have not attempted to classify the infections as trivial or serious. However, the percentage of serious infection, as evidenced by osteomyelitis, was about the same in the two series.
5. We cannot show that the local use of sulfonamide in these cases altered the incidence of infection.
6. In our two series of cases, early and careful débridement and irrigation were apparently the most important factors in preventing infection.