Southeast Asia is composed of 11 countries, characterized by diverse cultures, religions, and histories. These countries are:

• Brunei
• Myanmar (Burma)
• Cambodia
• Timor-Leste (East Timor)
• Indonesia
• Laos
• Malaysia
• Philippines
• Singapore
• Thailand
• Vietnam

This list includes both mainland countries (Cambodia, Laos, Myanmar, Thailand, Vietnam, and the western part of Malaysia) and island or maritime countries (Brunei, the eastern part of Malaysia, Timor-Leste, Indonesia, the Philippines, and Singapore)