As it sets about developing a new master plan, Northborough is in the market for professional help. Town Administrator John Coderre put out a statement Aug. 28 soliciting proposals from those qualified to help develop a policy-based, townwide plan, which he said would “define a community-based vision based upon broad-based public participation.” According to public documents, Northborough’s master plan was last updated in 1997. Respondents are expected to respond in writing and prove their qualifications to undertake the task, meaning “considerable experience in community design, land use planning, economic analysis, and citizen involvement/participation,” the statement said. Documents are available at Coderre’s office during business hours or on request by e-mail. Proposals are due by 2 p.m. Sept. 28.Lucas Phillips can be reached at email@example.com.