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The cervical nerves consist of 8 paired spinal nerves, C1 to C8, arising from the cervical spinal cord. These nerves function as the primary conduit for afferent and efferent signaling between the central nervous system (CNS) and the head, neck, and upper extremities. Unique to the cervical region, nerves C1 through C7 emerge from the spinal canal superior to their corresponding vertebrae. The C8 nerve emerges inferior to the C7 vertebra, marking the transition to the exit pattern observed in the thoracic and lumbar spine. The anterior rami of these nerves form the cervical and brachial plexuses, providing motor innervation to the diaphragm via the phrenic nerve and to muscles of the upper limb, alongside sensory innervation following a defined dermatomal pattern (see Image. Dermatome Map).[1][2] A detailed understanding of cervical nerve anatomy is essential for diagnosing and managing cervical radiculopathy, nerve entrapment syndromes, and traumatic injuries. Recognition of sensory and motor distributions facilitates lesion localization and guides interventions, including nerve blocks and neuromodulation therapies. Mastery of cervical nerve anatomy and function is critical in emergency, neurosurgical, and rehabilitative settings to optimize patient outcomes.