With the extensive use of living donor liver grafts in adult patients, controversy over small-for-size syndrome has escalated in recent years. Although several symptoms have been suggested as manifestations of the syndrome, small-for-size syndrome remains difficult to diagnose because these symptoms are neither specific nor inevitable. The occurrence of small-for-size syndrome also seems to depend on a number of recipient and graft factors. Potential pathogenic mechanisms include persistent portal hypertension and portal overperfusion. At present, several techniques are being explored in an attempt to ameliorate the impact of small-for-size syndrome. Recent experience suggests that the occurrence of small-for-size syndrome is multifactorial and that complications relating to small-for-size grafts should be examined in relation to a variety of graft, recipient, and technical factors.