How can I legalize a Belgian marriage certificate in Thailand?

To legalize a Belgian marriage certificate in Thailand, you should first have the document translated by an authorized translator recognized by the Belgian Embassy. It's recommended to get it notarized by the Ministry of Foreign Affairs and then register it at the Amphur (local civil registration office). For translation services, you may consider using services such as Express Translation or consult the list of recognized translators provided by the Belgian Embassy. Additionally, contacting the Embassy directly can be beneficial as they are responsive and helpful.