Section 797 — Agency — definition
Statutory text (Thai original)
อันว่าสัญญาตัวแทนนั้น คือสัญญาซึ่งให้บุคคลหนึ่ง เรียกว่าตัวแทน มีอำนาจทำการแทนบุคคลอีกคนหนึ่ง เรียกว่าตัวการ และตกลงจะทำการดังนั้นอันความเป็นตัวแทนนั้นจะเป็นโดยตั้งแต่งแสดงออกชัดหรือโดยปริยายก็ย่อมได้
Verbatim from the Royal Gazette / Office of the Council of State
English translation
Agency is a contract whereby a person, called the agent, has authority to act for another person, called the principal, and agrees so to act. Agency may be express or implied.
This English translation is provided for reference only and has not yet been firm-verified — always rely on the Thai original.
Firm annotation
Section 797 underpins all power-of-attorney work in Thailand. Three rules to remember: (1) agency to sell or mortgage immovables requires the same form as the underlying transaction — i.e., a written power of attorney registered at the Land Office (§798); (2) the agent cannot self-deal — buying from or selling to themselves on behalf of the principal is voidable; (3) the agent is bound by the principal's instructions and is liable for damage caused by exceeding them. For foreign clients abroad, a notarized + legalized power of attorney is the standard mechanism.