The Catholic Church in Malaysia, Singapore and Brunei (its two small Malay neighbors) is composed of a Latin Church hierarchy, joint in the transnational Episcopal Conference of Malaysia, Singapore and Brunei, consisting of three ecclesiastical provinces in Malaysia, a non-metropolitan archdiocese for Singapore, and a pre-diocesan Apostolic Vicariate for Brunei. There are no Eastern Catholic jurisdictions.
There is an Apostolic Nunciature to Malaysia as papal diplomatic representation (embassy-level) in the national capital Kuala Lumpur. In it the Apostolic Delegation (lower level) to Brunei is also vested.
There is a separate Apostolic Nunciature to Singapore (in the capital of the same name), into which are vested the Non-Residential Pontifical Representation for Vietnam and Apostolic Nunciature to the Association of Southeast Asian Nations (ASEAN, which all abovementioned states belong to, with others in the region).