A leave of absence letter is addressed to the board of directors of a company. The letter is written by another director who needs leave of absence from the board meeting due to some personal and professional reasons. Generally the letter is written in a polite way in order to inform the directors of a company regarding this. To make the letter authorize the director of a company who is on leave should mention the DIN number. It is a formal way to communicate with the other board member in respect of this matter.