Two cases of strangulated foramen of Winslow hernia are presented, seen at a single Institution during a 40-year period (1955-1995). In the first case, strangulation of the gallbladder was found, with gangrene of the latter and pus and gallstones spillage into the lesser sac. In the second patient, a strangulated segment of the terminal ileum with gangrenous destruction and pus in the bursa omentalis was found. The authors stress the necessity of opening the lesser sac through the gastrocolic ligament in cases of obvious gangrene or irreducibility of the hernia, in order to ensure the least traumatic reduction of the hernia, and to clean and drain the sac. An update of the literature is presented, and the diagnosis and treatment options of this rare entity are briefly discussed.