Concordian International School (Thai: โรงเรียนนานาชาติคอนคอร์เดียน, RTGS: Rong Rian Nana Chat Khonkhodian) is a Pre-K to grade 12 school located in Bang Phli District, Samut Prakan, Thailand. The school educates about 1050 students within the International Baccalaureate Organization programs. It is a trilingual international school in Thailand running the International Baccalaureate program. Concordian International School offers full immersion in English, Chinese and Thai from Pre-K until Grade 4, then a full English immersion program with Chinese and Thai as additional languages from Grade 5 to Grade 12.