This modified case study examines how the members of the British Columbia Teacher-Librarians' Association (BCTLA), a Provincial Specialist Association (PSA) of the British Columbia Teachers' Federation (BCTF), work together to advocate for strong school library programs headed by a credentialed school librarian. Since 2002, despite nullification of a collective bargaining agreement that mandated a ratio of school librarians to students, the province has maintained 70 percent of its school librarian positions. The researcher found that the BCTF provides the structure and megaphone for advocacy, while the members of BCTLA are responsible for the "boots on the ground" advocacy. Members of BCTLA are passionate about the role of school librarians despite significant challenges. Two-way communication between BCTF and BCTLA is vital. Additionally, a strong personal connection exists among BCTLA members. However, despite consistent advocacy efforts made by BCTLA and BCTF, the organizations face an uphill battle in terms of having their efforts impact policy. Librarian interest groups can use the structure of the union to promote school library issues. If a union is not available, school librarians can use influence-building techniques and professional associations to effectively advocate for strong school libraries. Union activity in support of school libraries offers a promising opportunity for library advocates.