BACKGROUND Compartment syndrome of the foot as a result of a calcaneal fracture has received only occasional consideration in the recent Emergency Medicine literature, yet it remains a challenging diagnosis to make. The devastating consequences of untreated compartment syndrome of the foot include clawing of the lesser toes, stiffness, chronic pain, motor weakness, neurovascular dysfunction, and fixed deformities of the foot. In addition to decreased quality of life, this also leads to lost time at work and lost wages. Calcaneal fractures can lead to devastating long-term disability that is often permanent and life-altering for patients suffering from this injury. Approximately 10% of patients with these fractures develop compartment syndrome of the foot. The pathogenesis of calcaneal fractures is well recognized, and the surgical treatment techniques continue to evolve. OBJECTIVE The objectives of this case report are to increase understanding of the pathophysiology of compartment syndrome and its short- and long-term consequences, to improve the ability to diagnose compartment syndrome, and to emphasize the need for emergent surgical treatment. METHODS A 37-year-old man sustained an isolated comminuted, extra-articular calcaneus fracture that resulted in compartment syndrome of the foot. The diagnosis required measurement of several compartments in the foot. He subsequently received emergent operative decompression and experienced a positive outcome. CONCLUSIONS Diagnosis of compartment syndrome of the foot is a clinical one, and diagnostic tools such as radiographic imaging and compartment pressure monitoring can help confirm the diagnosis. It is also important to understand the long-term sequelae of this injury and to involve a specialist early in the decision-making and treatment process.