The effects of glycerol-induced acute renal failure (ARF) and surgically induced chronic renal failure (CRF) on the pharmacokinetics and biliary excretion of rose bengal have been examined in the rat. Both the pharmacokinetics and biliary excretion of rose bengal were unaltered in either ARF or CRF. The latter results in CRF contrast with those of Tse et al (1976, Int. J. Nucl. Med. Biol. 3: 134-137) who reported decreased removal of the dye from blood and reduced biliary excretion. In addition, rose bengal behaves differently from bromosulphophthalein and indocyanine green whose hepatic uptake and initial biliary excretion are known to be decreased in ARF. The results suggest that rose bengal may have a hepato-biliary transport route which differs from that of bromosulphophthalein and indocyanine green, and the findings also emphasize the selective nature of altered organic anion uptake by the liver in ARF.