From April 1988 till May 1990 54 patients with symptomatic gallbladder stones were treated in the University Hospital Rotterdam-Dijkzigt with extracorporeal shock wave lithotripsy (ESWL) followed by oral administration of bile acids (urso- and chenodeoxycholic acid). These patients on average underwent 2 sessions of ESWL with an electromagnetic lithotriptor (Lithostar and Lithostar Plus, Siemens AG, Erlangen, FRG). Ultimate disintegration of stones was achieved in 50/54 (93%) patients. The best results were achieved in patients with a solitary gallstone (56% of these patients were stone-free 12 months after ESWL). Four per cent of the patients with 2-10 stones were free of stones 12 months after ESWL). Thirty-seven per cent of the patients suffered from biliary colics after ESWL and three patients developed pancreatitis. The administration of oral bile acids were complicated by transient diarrhoea in 20% of the patients. ESWL followed by oral bile acid therapy is a relatively effective and safe therapy for a highly selected population of patients with gallbladder stones.