The acute compartment syndrome is caused by bleeding or edema in a closed muscle compartment surrounded by fascia and bone. It is characterized by increased intracompartmental pressure and decreased tissue perfusion. Well-known causative incidents are acute trauma and reperfusion after treatment for acute arterial obstruction. Most commonly the lower leg is involved. Inadequate therapy of the syndrome usually leads to muscle ischemia, rhabdomyolysis, and renal insufficiency. Perioperative morbidity and mortality are high. Although compartment syndromes can be caused by various factors, up until now no comparative studies have been published on clinical outcome of compartment syndromes of different origin. In this retrospective study we analyzed 40 successive cases of fasciotomy for acute lower leg compartment syndrome to study whether different causes of the syndrome lead to different clinical outcomes. We also studied other predictive factors for clinical outcome. The causes for the compartment syndromes were trauma, vascular deobstruction, cardiac surgery, and gastrointestinal surgery in lithotomy position. Clinical outcome showed a mortality of 15% and serious overall morbidity. Multivariate analysis showed the only significant predictive determinant of outcome to be the age of the patient. Fasciotomy for acute compartment syndrome is associated with serious morbidity and mortality. No correlation between causative factors and clinical outcome could be found.