Objective. Although a number of pretransplant urologic evaluations have been recommended in the literature, their efficacy has not been validated. This study was undertaken to evaluate a standardized urologic diagnostic protocol for potential adult transplant recipients. Methods. One hundred consecutive adult transplant candidates were prospectively evaluated with a complete history and physical examination, renal ultrasonography (US), voiding cystourethrography (VCUG), urinalysis, and urine culture. Other diagnostic studies including cystoscopy and retrograde pyelography were performed as indicated. Results. Urologic malignancies were diagnosed in 3 patients that included Stage A2 prostate cancer, Stage TA transitional cell carcinoma of the bladder, and Stage 11 renal cell carcinoma. The only significant abnormality detected by renal US was renal cell carcinoma in 1 patient. Twenty-six individuals had VCUG abnormalities, but these could not be predicted based on patient characteristics. However, VCUG was normal in all nondiabetic patients without voiding symptoms or a history of urinary tract infections. Thirteen patients had hematuria and were evaluated with cystoscopy and retrograde pyelography. One individual (7.6%) had a significant abnormality (bladder tumor) detected during cystoscopy. Retrograde pyelography demonstrated no clinically significant abnormalities in this patient group. Eighteen patients had sterile pyuria and underwent similar endoscopic evaluation. Cystoscopic examination was normal in all these individuals, and retro grade pyelography showed either normal or clinically insignificant papillary necrosis. Conclusions. Although renal US has a low diagnostic yield, all adult transplant candidates should undergo this study because of the high prevalence of renal cell carcinoma in this cohort. VCUG also should be performed prior to transplantation, but it may be omitted in nondiabetic patients without voiding symptoms or a history of urinary tract infection. Transplant candidates with hematuria warrant an endoscopic evaluation, although this may not be necessary in individuals with sterile pyuria. © 1993.