Gallstone recurrence was evaluated in 184 patients exhibiting complete stone disappearance after successful extracorporeal shock-wave lithotripsy (ESWL) and concomitant oral bile acid therapy. Follow-up examinations conducted 6-43 months after termination of adjuvant bile acid therapy revealed recurrent calculi in 40/184 (21.7%) patients (27 females, 13 males, p < 0.01; 13 patients with solitary, 27 patients with multiple stones) after a median stone-free period of 11 months (range 1-33 months; mean +/- SD, 13 +/- 8 months). Therefore, an overall probability of stone recurrence of 11.8% was observed 12 months after complete stone disappearance had been confirmed sonographically and bile salt therapy terminated, and a probability of 25.5% after 24 months. Gallstone reformation occurred in 30/146 (20.5%) patients with initially solitary and 10/38 (26.3%) patients with multiple calculi [not significant (NS)]. Only 3/40 (8%) patients with recurrent calculi reported biliary colic. Sonographic gallbladder contractility values acquired at the time recurrent stones were detected did not show any significant differences, compared with the data obtained in the pretreatment examinations; neither were any differences noted between the patients with gallstone reformation and those who remained stone-free. In 20/33 (61%) patients with recurrent stones who opted for further conservative retreatment (ESWL and/or oral litholysis), complete stone disappearance was achieved a second time. The recurrence rates achieved within the first 3 yr after successful shock-wave lithotripsy of biliary calculi cover a range similar to the rates noted after dissolution therapy.