1. One per cent beta-propiolactone has been shown capable of sterilizing animal tissues which have been either artificially infected with vegetative and spore-forming bacteria or taken from the animals during the stage of bacteraemia or viraemia. It also sterilizes leukaemic-infected splenic tissue.
2. The depth of drug penetration did not exceed 1.5 millimeters in compact tissues (liver and spleen) and three millimeters in cancellous bone. Thus, compact tissues to a thickness of three millimeters and cancellous bone to a thickness of six millimeters can be satisfactorily sterilized.
3. Good results were obtained in all of the cases in which beta-propiolactone sterilized bone was used (fifty operations).
4. A bone bank in which material sterilized with beta-propiolactone is used has been established.
5. The simple, rapid, and inexpensive chemical method of the sterilization of contaminated bone described in this paper can be readily utilized in small hospitals.