Foreigners staying in Thailand under Section 15 (diplomat, official) and wishing to extend their stay in the case of applying for a job must apply for a visa
Foreigners wishing to extend their stay in the case of investment must apply for a visa extension under Section 15 of the Immigration Act 1979 (diplomat, official)
Foreigners staying in Thailand who are assigned by a foreign government, with the Thai Government’s approval, to perform their duties or missions in the Kingdom of Thailand
Foreigners staying in Thailand with the purpose of performing a duty or mission in the Kingdom of Thailand under an agreement made by the Thai government with a foreign Government.