Michael George DeSombre[1] (born 1968) is a partner of Sullivan & Cromwell[2] and a former United States Ambassador to the Kingdom of Thailand.

DeSombre joined Sullivan & Cromwell LLP in 1995 and became a partner of the law firm in 2004, leading its mergers and acquisitions practice in Asia,[3] with clients including Goldman Sachs, Anheuser-Busch InBev and Credit Suisse.

The organization focuses on tax reform[5][6] and proposed replacing FATCA with territorial taxation for individuals to the House Ways and Means Committee, as part of a 2017 executive order to review the Dodd-Frank Act.

[12] DeSombre has stated that his Office will primarily encourage the economic partnership between the two countries, with focus on American investment and Thailand's infrastructure projects and supply chains.

[3][21] Prior to assuming his post in Bangkok in 2020, DeSombre lived in Hong Kong, residing in Asia for two decades.