This chapter considers the compartmentatlization of the arm (anterior and posterior) along with the contents; the median nerve, the brachial artery and the profunda brachii artery. The cubital fossa is considered along with its borders and contents. The anatomy of the elbow joint is discussed along with the combined superior radioulnar joint and their biomechanics. The structure of the elbow ligaments explains the childhood condition of ‘pulled elbow’. Ossification and the origins and insertions of the humerus are included.