This article deals with the Cape Town Convention and Aircraft Protocol. The introduction shows the current status of the Cape Town Convention and Aircraft Protocol around the world, and defines the Korean translation of "international interests" which is used in the Convention and Protocol. Part II introduces UNIDROIT, which drafted the Cape Town Convention and Aircraft Protocol, and reviews the background, history and characteristics of the Cape Town Convention and Aircraft Protocol. Furthermore, it shows expected benefits that Korea could get if Korea would join the Cape Town Convention and Aircraft Protocol. Typical benefits are discounts of premium rates for aircraft mortgage loans and simple procedures for the international transfer of aircraft mortgages. Part III investigates the registration on the International Registry under the Cape Town Convention and Aircraft Protocol. It also analyzes the relationship between the filing on the domestic aircraft registry and the registration on the International Registry. The object that falls in the scope of application of the Cape Town Convention and Aircraft Protocol may be registered on the International Registry. Therefore it examines the scope of application of the Convention and Protocol, first in terms of the parties of the registration and secondly, in terms of the object of the registration. Moreover, it reviews the operation of the International Registry, the effectiveness of the registration on the International Registry, registration fees, discharge of registration, and duration of registration. Part IV explains important declarations including the declarations that the OECD requires for the Cape Town Convention discount. For the Cape Town Convention discount, a contracting state is required to declare that any remedy available to the creditor under the Convention may be exercised without leave of court (Article 54(2) of the Convention), or to declare that a creditor who adduces evidence of default by the debtor, pending final determination of its claim, may obtain from a court speedy relief (Article 13 of the Convention). In addition, a contracting state is required to declare that upon the occurrence of an insolvency-related event, the insolvency administrator or debtor shall give possession of the aircraft to the creditor no later than 60 days (Article XI Alternative A of the Protocol) and the creditor may be entitled to exercise a de-registration and export request authorization (Article XIII of the Protocol). In conclusion, if Korea would join the Cape Town Convention and Aircraft Protocol, Korean airlines could reduce financing costs for leasing or purchasing aircraft. Korean airlines usually fulfil obligations very well and there are few cases of default or bankruptcy. Thus, there would be more plus than minus if Korea would join the Cape Town Convention and Aircraft Protocol.