The purpose of the Friends of Plymouth District Library is as follows:
- To maintain an association of persons interested in books and libraries
- To assist in promoting knowledge of and participation in library needs
- To aid in providing funds to meet special library needs
- To support and cooperate with the library in developing services and facilities for the community
- To stimulate the gift of books, magazines, periodicals, desirable collections endowments and bequests
- To provide a channel for individuals and organizations to express ideas and make suggestions for library use and service
- To do all things to promote and foster the betterment of library services to all the Plymouth community