Mr. Say Thearith is working with Garment Manufacturers Association in Cambodia (GMAC) since 2013. He is currently working as Assistant to Labour Officers; he is responsible for assisting labour officer to resolve the labour dispute, organizing labour law training course and other daily tasks in Labour Department.

In 2011, He worked as volunteer at Documentation Center of Cambodia (DC-Cam) in Family Tracing Project. Being the volunteer, he was responsible for reading a millions of confession and other documents during Khmer Rouge regime in order to look for names of people who might have died under the Khmer Rouge.

Mr. Say Thearith graduated the bachelor degree from Norton University, major in Law in 2012. During his academic, he attended many workshops related to law such as Client Counseling Workshop and Advocacy Skill Workshop, ect. Moreover, he received a Certificate of Merit in Writing Competition, which was held at Norton University for all majors student, as the runner up in writing paragraph.