An adjustable cervical collar designed to accommodate a broad range of prospective wearers with unique physical attributes, and to restrict the movements of the wearers cervical spine, including rotation, flexion, extension, and lateral bending. The cervical collar includes a front portion and back portion, which may be adjusted in relation to one other to vary the circumference of the cervical collar. The front portion includes upper and lower plastic portions which may be adjusted to vary the height of the cervical collar, and a front thoracic extender which may be adjusted to achieve a desired restrictiveness of flexion movement. The back portion includes occipital and back thoracic extenders which may be adjusted to achieve a desired restrictiveness of extension movement. The adjustable features may be operated independently of one another. The adjustable features include locking means to ensure that the cervical collar is securely applied to the wearer.
