Tracts of the medial motor system regulate axial or truncal muscles involved in maintaining posture, balance, automatic gait-related movements, and orientating movements of the head and neck. Unlike the lateral motor system, the tracts in this system primarily project bilaterally on interneurons within the spinal cord. This makes it difficult to test each tract individually in the clinical system. We will briefly review the four tracts of the medial motor system beginning with the anterior corticospinal tract.