Around the world, ประสุทธิ์ (ประสุทธิ์ 
) is a very rare largely boy's, but infrequently feminine forename. The given name ประสุทธิ์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare largely boy's, but seldom girly name. More prevalently, ประสุทธิ์ is the last name as well as the forename.