Although nonoperative management is the standard initial treatment in children with splenic injury, this therapeutic option has been exercised infrequently in adults. Over the past two years we have hospitalized and observed 11 hemodynamically stable adults with splenic trauma and no other significant injury. Ten patients sustained blunt trauma localized to the left upper quadrant, and one patient was stabbed in the left flank. Eight patients were normotensive on hospital arrival, while three had an initial systolic blood pressure of 90 to 98 mm Hg. All patients remained normotensive after receiving 2 liters of crystalloid fluid IV. Nine patients had an initial hemoglobin level of 11.1 to 14.0 gm/dl, and two a level of less than 10 gm/dl. Liver-spleen scan done in ten patients yielded true-positive results in eight, false-positive results in one, and false-negative results in one. In the 11th patient, a celiac arteriogram showed a splenic defect. Three patients had laparotomy 27 to 43 hours after hospitalization, owing to a decreasing hemoglobin concentration; one required partial splenectomy. Eight patients were successfully managed nonoperatively; only one required blood transfusion, and all tolerated oral alimentation by the second hospital day. All patients were discharged by the 12th hospital day. Nonoperative management can be successfully applied to adults with isolated splenic trauma.