Diaphyseal fractures of the tibia are occasionally associated with compartmental syndrome of the leg. Current treatment includes surgical decompression of all involved compartments, debridement of nonviable muscle tissue, and skeletal stabilization. Numerous methods of fasciotomy have been described in the literature, with most surgeons favoring the two-incision method. The single-incision, 4-compartment fasciotomy is an alternative method but has received little attention in the orthopaedic literature. We detail the surgical technique for the single-incision, 4-compartment fasciotomy of the leg without fibulectomy and report its usage in the management of diaphyseal tibial fractures with compartmental syndrome.