Our Bylaws at Unity Church are probably atypical of other Unitarian Universalist congregations. Yes, our board, by a three-fourths vote may amend the Bylaws and, at congregational meetings, the congregation can do so as well. This quirky feature is certainly not necessary in order to implement Policy Governance. I can't see any reason why the Policy Governance model wouldn't work just as well with the congregation holding sole power to change the bylaws—it just means more congregational meetings. Some typical changes in Bylaws to facilitate the adoption of Policy Governance are reduction of the number of trustees to around seven (we have nine) and the streamlining of officers to usually just a chair and secretary (other officers that are typical of Operations Boards are not necessary on Policy Governance Boards.) In some congregations everyone may want to vote on such things, in others such technical issues are of little interest and gladly delegated back to the Board.
Policy Governance assumes that there is a body charged with governance, i.e., the Board. If the congregation has not delegated governance powers through Bylaws to a Board then no model of governance is necessary.
Carver's chapter called "Resource B, Bylaws" (p.222) in the 1997 edition of Boards That Make a Difference may be helpful.
—Gretchen C. Dorn, Unity Church-Unitarian, St. Paul, MN, 08/10/99