Four hundred ninety-five patients undergoing peripheral arterial percutaneous transluminal dilatation (TLD) with the Gruntzig balloon catheter were studied prospectively to determine which factors could be used to predict a successful result from the procedure. Ten variables were recorded before the TLD. The procedure was considered a success at follow-up if both the clinical grade and the objective vascular laboratory results improved. The results of a logistic discriminant function analysis showed that three variables were associated with success of a TLD at 3 months: the site of the TLD, the severity of the lesion (i.e., stenosis or occlusion), and the runoff. With these results, logistic regression analysis was used to estimate the chances of a successful result for all combinations of these significant variables. It is concluded that the early result of a TLD is determined by the site of the TLD, the severity of the lesion, and the runoff. A table of the estimated chances of success for any combination of these variables has been constructed and accurately describes our patient population.