The purpose of this study was, using consensus methodology, to document current understanding of contrast media nephrotoxicity (CMN) and to identify areas where there is disagreement or confusion. To draw up guidelines for avoiding CMN based on the current understanding of the condition established by the survey. One hundred sixty-four statements were mailed to 148 members of the European Society of Urogenital Radiology (ESUR) and to 48 experts in the field of CMN. They were asked about the definition, clinical features, predisposing factors and pathophysiology of CMN and about prophylactic measures. The importance of the statements was rated on a scale from 1 to 10 (1 least important, 10 most important). Fifty-three members (38%) and 23 experts (48%) responded. Both groups considered that an increase in serum creatinine that peaks within 3-4 days and a decrease in creatinine clearance are the most important (rating > 7) features of CMN. Enzymuria was not considered important (rating < 6). Pre-existing renal insufficiency, diabetic nephropathy, dehydration, congestive heart failure, concurrent administration of nephrotoxic drugs and the dose and type of contrast media were considered to be risk factors. Reduction in renal perfusion and damage to tubular cells were considered the main factors in the pathophysiology of CMN (rating > 6). Hydration and the use of low osmolar contrast media were thought to minimize the incidence of CMN (rating > 6). The majority of the responders (84.6% of members and 95.5% of experts) believe that the incidence of CMN in patients with normal renal function is less than 5%. Of the members, 62.5%, and 35.3% of experts, believe that the incidence of CMN is 20-30% in the presence of risk factors. There was disagreement about the definition of CMN, the threshold dose of contrast media above which renal complications may develop, the safe period between repeat injections, the relevance of contrast media renal retention shown on CT and whether contrast media have long-term effects on renal function. The survey showed good understanding of CMN among those who answered the questionnaires, although areas of disagreement remain which require further research. Simple guidelines are proposed.