&NA;Sigmoid volvulus is not a common disease in the United States. Thus, a good understanding of this disease can be obtained only by compiling the experiences of many physicians. The purpose of this paper has been to review the reported clinical experience with sigmoid volvulus throughout the world with sigmoid volvulus. This has revealed two clinical patterns of presentation. In Asia, Eastern Europe, and much of Africa and Brazil, sigmoid volvulus is a common cause of intestinal obstruction, frequently occurring in middle‐aged men living in rural areas. In English‐speaking countries, it is a rare cause of intestinal obstruction. In these countries the patient with sigmoid volvulus is typically old, male, black and institutionalized.The pathogenesis of sigmoid volvulus has been attributed to many etiologies. A single mechanism combining two features probably provides the basis for these theories. A narrow mesocolon at its parietal attachment produces an excellent pivot point for a redundant sigmoid colon, predisposing the individual to sigmoid volvulus. Whether in Africans eating coarse fiber diets, in Brazilians with Chagas' disease, or institutionalized Americans, the combination of a narrow mesosigmoid parietal attachment and redundant colon is nearly always found in patients in whom sigmoid volvulus develops.