Bilateral agreements facilitate the reciprocal certificate of airworthiness of civil air products imported/exported between two signatory States. A bilateral airworthiness agreement (BAA) or a bilateral aviation safety agreement (BASA) with airworthiness implementation procedures (APIs) provides for technical cooperation between the FAA and its partner authorities in the field of civil aviation. Work procedures are a type of agreement with a foreign CAA with which the FAA has not entered into a bilateral agreement. They are used to define the methods used by the FAA`s Aircraft Certification Service to assist another state in authorizing aeronautical products and articles exported from the United States to that state. This Agreement shall enter into force upon signature and shall remain in force until it is denounced by a Contracting Party. Such denunciation shall be effected by a sixty-day written notification addressed to the other party. Such denunciation shall also entail the termination of all existing enforcement procedures implemented in accordance with this Agreement. This Agreement may be amended by the written agreement of the Parties. Civil aviation authorities may terminate or modify individual implementation procedures. DESIRING to strengthen cooperation and improve efficiency in civil aviation security, wishing to promote aviation safety and environmental quality, the bilateral aviation safety agreements provide, in addition to the certificate of airworthiness, for bilateral cooperation in a wide range of aviation areas, including maintenance, flight operations and environmental certification.