Hallux valgus (HV) is a complex deformity of the great toe that develops as a result of changes in the anatomy of the first ray of the foot. The first ray of the foot serves as a single functional foot unit with bony structures consisting of the phalanges of the great toe, sesamoid bones, first metatarsal, and medial cuneiform. The stability of the first ray depends on the balance between static and dynamic anatomical structures. Loss of this balance between anatomical structures plays a role in the development of HV. This chapter elucidates the anatomical features of the first metatarsocuneiform and first metatarsophalangeal joints of the first ray.