A prospective study was performed to assess the role of preoperative ultrasonography in predicting failed or difficult laparoscopic cholecystectomy. Fifty patients underwent detailed preoperative ultrasound examinations. The number and size of calculi, evidence of acute or chronic cholecystitis, gallbladder morphology, and the presence or absence of aberrant anatomy were documented. A comparison was made of the surgical outcome and the ultrasound findings in each patient. Six patients were converted to open cholecystectomy because of inflammatory changes in the gallbladder. The preoperative ultrasound studies in 5 of these patients demonstrated evidence of cholecystitis and cholelithiasis. Gallbladder wall thickening and contraction were also seen. Five gallbladder resections had intraoperative difficulties; preoperative ultrasonography demonstrated a thickened gallbladder wall in 2. Of 31 uneventful cases, 7 had evidence of gallbladder wall thickening and/or contraction. There were no ultrasound features that identified between the unsuccessful, difficult, or uneventful laparoscopic cholecystectomies. We conclude that detailed preoperative ultrasound evaluation of the gallbladder in patients destined for laparoscopic cholecystectomy is of little value in screening for difficult or unsuitable cases.