This chapter stipulates the rules for the alteration of real rights, focusing on the publicity principle for immovable property through registration. It details the modes of alteration for both immovable and movable property, distinguishing between changes based on legal acts (where registration or delivery is generally required) and those not based on legal acts. The chapter emphasizes the critical distinction between the cause of an alteration (e.g., a contract) and the alteration itself, a principle established to correct historical confusion. Furthermore, it underscores the significance of the publicity principle, particularly the public trust effect of registration, for protecting transaction security and third-party interests.