Controversy continues regarding risk factors for nephrotoxicity and the possible differences in nephrotoxicity rates associated with the aminoglycosides commonly used in clinical practice. Review of published data, including 27 comparative clinical studies, indicates the following: sensitive markers of tubular toxicity do not correlate directly with clinically significant diminution in glomerular filtration rate; of all the proposed risk factors, few are consistently found; despite numerous studies, some with potential drawbacks, no current aminoglycoside has been shown to be consistently and conclusively less nephrotoxic than another; and, as per a previous recommendation, the choice of an aminoglycoside should not be made on the basis of nephrologic criteria.