from the newest edition of Selectmen Handbook, easily found by anyone on Massachusetts Municipal Association website.
The long-held view that town managers have more authority than town administrators has no basis in state law. Some town manager positions have fairly modest authority, and some town administrators have significant authority.
The “strong town manager” reference is also a matter of perspective or individual town experience with the position. Some ways in which the position could be considered “strong” are the extent of appointment authority, authority for the direction of the budget and capital plan process, and assumption of certain duties previously assigned to the Select Board (e.g., approval of payments).
Each community has approached this question differently, and the expectations for these positions by town leaders have evolved over time, so there are myriad job descriptions for such positions. Examples from which to draw ideas are readily available on town websites that include bylaws and charters.