On Nov. 18, 2012, during US President Barack Obama’s visit to Thailand, Prime Minister Yingluck Shinawatra announced that her country would join the Proliferation Security Initiative (PSI). Thailand is the fifth of the 10 members of the Association of Southeast Asian Nations (ASEAN) to join the PSI, after Singapore (2004), the Philippines (2005), Brunei Darussalam (2008), and Cambodia (2008); the non-participating countries are Indonesia, Malaysia, Myanmar, Laos, and Vietnam.