Mass. Gen. Laws ch. 30 § 25B
No officer or employee of the commonwealth may travel out of state at public expense except in accordance with rules and regulations established by the commissioner of administration for the expenditure of funds for travel out of state by employees of the commonwealth, and except with the prior written approval of his appointing authority, and, in the case of a department, office, commission, board, or institution within any of the executive offices established by chapters 6A and seven upon the prior written approval of the secretary having charge of such executive office. The officer approving such out-of-state travel shall forthwith file notification of such approval with the budget director and the comptroller.
Mass. Gen. Laws ch. 30, § 25B