Dipropyl [35S]-sulphoxide was administered by gavage (4.24 mmol/kg body weight) to adult male Wistar rats and the placement of radioactivity about the animal examined at 4, 8 and 12 hours post-dosing. Widespread and diffuse distribution throughout soft tissues was observed with the largest amounts of radioactivity being found within the liver (3.2% dose at 4 h) and kidney (1.3% dose at 4 h). Activity levels declined over the 12 hour experimental period. This distribution pattern is discussed and compared with results previously reported for dimethyl sulphoxide.