R.I. Gen. Laws § 45-32-45

Two (2) or more communities may jointly exercise the powers granted under chapters 31 — 33 of this title and, in that case the planning commissions, legislative bodies, and agencies may hold joint hearings and meetings, or the legislative bodies of the communities, acting separately, may each designate the agency of one of the communities to act as the agency of all the communities interested. In this event, the designated agency shall cooperate with the planning commission of each community in formulating redevelopment plans, and, whenever a redevelopment plan is submitted to the legislative body, each planning commission shall report to the legislative body of its community within thirty (30) days on the redevelopment plan and its conformity to the master or general plan of the community.