Acute compartment syndrome of the extremities is a surgical emergency and a rapid diagnosis and immediate surgical treatment are essential for the outcome. The cause is an increase in the tissue pressure inside a muscle compartment enclosed by fasciae and the resulting disruption of microperfusion. This can have potentially disastrous consequences, such as loss of the extremity due to extensive tissue necrosis or a threat to life due to infectious complications. Although mostly triggered by trauma, a multitude of other causes can lead to the formation of a compartment syndrome, so that a basic knowledge of this condition is of great importance not only for trauma surgeons. This is particularly true because a timely treatment necessitates rapid diagnosis and evaluation of the indications. This article provides an overview of the underlying pathophysiology, the causes, the symptoms and the treatment of acute compartment syndrome.