A commitment letter (also called a mandate letter) to be sent by a bank to be appointed as an arranger in relation to a proposed syndicated project finance facility. It sets out the terms on which the arranger will arrange the loans or other facilities to be made to a project borrower. It includes optionality to make it either a "best efforts" arranging mandate or an underwritten mandate. The project sponsor (on behalf of the borrower) grants the mandate by signing and returning the letter.