The Libraries Regulation (Part 3, Municipal Boards and Intermunicipal Library Boards, 13(1) Plan of Service) requires boards to have a current plan of service that is on file with the provincial Ministry. Library boards are responsible for planning and they can choose the approach that works best for their situations. The Public Library Services Branch (PLSB) highly recommends a process called "Strategic Planning for Results." It is defined in the book Strategic Planning for Results by Sandra Nelson, published in 2008 by ALA.
This approach is:
Designed specifically for public libraries, by leading library professionals
Focused on the community and community needs
Straightforward and easy to follow, with detailed instructions
Client Services staff are available to assist you with this process. You can read more at the Plan of Service section of the PLSB website.
Information on conducting a needs assessment will help you construct your Plan of Service.