Brunei joined ASEAN on 7 January 1984, one week after resuming full independence, and gives its ASEAN membership the highest priority in its foreign relations. Brunei joined the United Nations in September 1984. It also is a member of the Organisation of Islamic Cooperation (OIC), the Asia-Pacific Economic Cooperation (APEC) forum and the Commonwealth of Nations. Brunei hosted the APEC Economic Leaders' Meeting in November 2000. In 2005 it attended the inaugural East Asia Summit.
Brunei has a number of diplomatic missions abroad and has close relations with Singapore, sharing an interchangeable currency regime as well as close military relations with the latter island-state. Aside from relations with other ASEAN states, of which the Philippines, Indonesia, and Malaysia are key partners, Brunei also has extensive relations with the Islamic and Arab world outside its region.
Brunei became a member state of the United Kingdom Commonwealth in 1984, ASEAN, the United Nations and the Organisation of Islamic Cooperation) in 1984, the Organisation of Islamic Cooperation, a major player in BIMP-EAGA in 1994., a founding member of the World Trade Organization (WTO) in 1995, Since 2009 Brunei and the Philippines signed a memorandum of understanding (MOU) that seeks to strengthen the bilateral co-operation of the two countries in the fields of agriculture and farm-related trade and investments.
Brunei has been a fully independent member state of the Commonwealth of Nations since 1 January 1984, when it regained independence, having been under British protection and suzerainty since 1888.
Bruneians can take an appeal to the Judicial Committee of the Privy Council in London in civil cases only. The Judicial Committee of the Privy Council reports back to the Sultan in cases originating from the courts of Brunei.
Australia and Brunei Darussalam enjoy a warm, and increasingly diverse bilateral relationship. Australian servicemen liberated Brunei from Japanese occupation in June 1945. A memorial marking this event can be found at Muara Beach and is the venue for the annual ANZAC Day ceremony organised by the High Commission. Both countries are also participating in the Trans Pacific Partnership (TPP) negotiations which commenced in 2010, with participants aiming to conclude an agreement which will serve as a building block for Asia Pacific economic integration.
Brunei has a high commission in Canberra, and Australia has a high commission in Bandar Seri Begawan. Both countries are full members of the Commonwealth of Nations. Relations between the two countries were established in 1984 when Australia became one of the first countries to establish diplomatic relations with Brunei.
Both countries established diplomatic relations on 15 April 2012.
Bilateral relations are excellent between the two predominantly moderate Muslim nations. They are both members of OIC, the Commonwealth and NAM and share common views on regional and international issues. Brunei recognised Bangladesh quickly with other Southeast Asian countries and Bangladesh established a residential High Commission in 1985, although it was closed down from 1988 to 1997 due to financial constraints. Brunei has a High Commission located in Dhaka. Brunei actively supports Bangladesh's candidacy for different regional and international organisations.
Canada established diplomatic relations with Brunei Darussalam on 7 May 1984, following Brunei's independence. Brunei has a High Commission in Ottawa, and Canada has a High Commission in Bandar Seri Begawan. Like Brunei, Canada is a full member of the Commonwealth of Nations..
Brunei has a High Commission in New Delhi, and India has a High Commission in Bandar Seri Begawan. Both countries are full members of the Commonwealth of Nations. Relations have been established since 10 May 1984.
Republic of Indonesia established diplomatic relations with Brunei Darussalam on 1 January 1984. Brunei Darussalam was recognised by Jakarta on independence in 1984, with Indonesia dropping any claims on the Sultanate in the process.
Both countries established diplomatic relations since January 1984 with Brunei has a High Commission in Kuala Lumpur, and Malaysia has a High Commission in Bandar Seri Begawan. Like Brunei, Malaysia is a full member of the Commonwealth of Nations.
The Bruneian High Commission in Kuala Lumpur is accredited to New Zealand, while the New Zealand High Commission in Kuala Lumpur is cross-accredited to Brunei. Relations has been established since 5 May 1984 and have always been friendly and positive with such co-operation in education trade and defence.
Pakistan has a High Commission in Bandar Seri Begawan and Brunei has a High Commission in Islamabad. Pakistan initially hesitated to recognise the country at first since its close relations with Malaysia which what they considered as part of the Federation of Malaysia but later established relations on 9 February 1984 when Malaysia established relations with the country.
Relations between Brunei and the natives of a then divided Philippines under a classical era started since the 10th to 13th centuries and continued even under the colonial regimes. Relations continued through the Sultanate of Sulu. Post World War II relations between the two countries has been re-established since January 1984. In April 2009, Brunei and The Philippines signed a memorandum of understanding (MOU) that seeks to strengthen the bilateral co-operation of the two countries in the fields of agriculture and farm-related trade and investments. The MOU further strengthened bilateral co-operation between the two Southeast Asian countries, particularly in the fields of agriculture and farm-related trade and investments. The two countries have agreed to co-operate in plant science, crops technology, vegetable and fruit preservation, biotechnology, post-harvest technology, livestock, organic agriculture, irrigation and water resources and Halal industry. Brunei is viewed by the Philippines as a key ASEAN and Islamic ally. While Brunei view the Philippines as an ASEAN and Christian ally with a Muslim minority. 
Brunei maintains an embassy in Moscow, the Russian embassy in Brunei was established in March 2010.
The official relations between the two countries has been established since 1984. Brunei and Singapore agreed to have Singapore train its armed forces with Brunei. Like Brunei, Singapore is a full member of the Commonwealth of Nations.
In August 2005, Brunei's Foreign Affairs and Trade Minister, Prince Mohamed Bolkiah arrived in Singapore for a three-day visit during which the two countries signed an agreement to eliminate double taxation, paving the way for further bilateral trade and investment.
Brunei has an embassy in Seoul South Korea, which has an embassy in Bandar Seri Begawan. South Korea established diplomatic relations with Brunei on 1 June 1984 right after the country gained independence from the United Kingdom on 1 January on that year.
In 1888, Brunei became a British protectorate, gaining its independence from British protection less than 100 years later in 1984.
The UK and Brunei have a long-standing and strong bilateral relationship, particularly on defence co-operation, trade and education. The UK continues to play a strong role in developing Brunei’s oil and gas sector, and the Brunei Investment Agency is a significant investor in the UK, with their largest overseas operations in the City of London. The UK remains the destination of choice for Bruneian students, with about 1,220 of them enrolled in higher education in the UK in 2006-07. The Brunei Royal family have strong ties to the UK, more specifically 'Birchwood' a small dingy suburb of Warrington.
The US welcomed Brunei Darussalam's full independence from the United Kingdom on 1 January 1984, and opened an embassy in Bandar Seri Begawan on that date. Brunei opened its embassy in Washington, D.C. in March 1984. Brunei's armed forces engage in joint exercises, training programs, and other military co-operation with the USA memorandum of understanding on defence co-operation was signed on 29 November 1994. The Sultan of Brunei visited Washington in December 2002.
Relations between the two countries has been established since 29 February 1992. Brunei has an embassy in Hanoi, and Vietnam has an embassy in Bandar Seri Begawan. Relations between the two countries have always been friendly especially in the political field.