Massachusetts Constitution Amendments Art. II, § 4

Every city and town shall have the power to amend its charter in the following manner: The legislative body of a city or town may, by a two-thirds vote, propose amendments to the charter of the city or town; provided, that (1) amendments of a city charter may be proposed only with the concurrence of the mayor in every city that has a mayor, and (2) any change in a charter relating in any way to the composition, mode of election or appointment, or terms of office of the legislative body, the mayor or city manager or the board of selectmen or town manager shall be made only by the procedure of charter revision set forth in section three.

All proposed charter amendments shall be published and submitted for approval in the same manner as provided for adoption or revision of a charter.