The Massachusetts Library Staff Association (MLSA) is a left-of-center government worker union representing more than 500 library workers in 31 municipalities in Massachusetts. ¹ It is Local 4928 of the American Federation of Teachers (AFT), and affiliated with AFT Massachusetts and the AFL-CIO. ¹

Organization

The Massachusetts Library Staff Association is an American Federation of Teachers (AFT) local union representing librarians in public libraries across Massachusetts.  ¹ It claims more than 500 members in 31 municipalities across the Commonwealth, including the Boston Public Library.  ¹

The MLSA is affiliated with the AFT’s Public Employees division. ² It is one of the few AFT-affiliated local unions representing public librarians across the country.  ³ The AFT has described the MLSA a source of “best practices” in its ongoing campaign to organize public librarians. ^{3  4}

As of 2025, the president of MLSA was Patricia K. Kelly. ⁵

Financials

In 2023, the MLSA collected $373,168 in dues from its members. ⁶

It typically does little spending on its own behalf, with more than 85 percent of its $387,104 of expenses in 2023 listed as “payments to affiliates.” ⁶

Advocacy

The Massachusetts Library Staff Association promotes left-of-center social views and public policies. ⁷ It opposes efforts to expand educational choice in Massachusetts, which it characterizes as “the far right’s assault on public education.” ⁸

It operates four internal identity-based groups or caucuses: “LGBTQIA+,” “BIPOC,” “Censorship,” and “Workplace Safety.” ⁹

It supports state-level programs to forgive or restructure student debt, and supported the Biden administration’s efforts to eliminate student debt via federal regulation or executive order. ¹⁰

In December 2024, MLSA President Patricia Kelly was one of 22 “senior women leaders of the labor movement” to co-sign a letter to President Joe Biden urging him to “certify and publish the Equal Rights Amendment (ERA) in the Constitution.” ¹¹ While Biden declared in January 2025 that the ERA was “the law of the land” and “the 28^th Amendment to the Constitution,” his declaration was broadly understood to have no legal force as the certification of amendments is the responsibility of the Archivist of the United States, who is bound by a Department of Justice opinion which held that the amendment expired after a 1982 deadline to ratify it was missed. ¹²

1. Massachusetts Library Staff Association. Accessed September 22, 2025. https://mlsa.ma.aft.org/.
2. “About AFT Public Employees.” Massachusetts Library Staff Association. Accessed September 22, 2025. https://mlsa.ma.aft.org/about-us/about-aft-public-employees.
3. “The American Federation of Teachers Is All in for Libraries!” AFT Massachusetts , May 12, 2023. https://mlsa.ma.aft.org/american-federation-teachers-all-libraries.
4. “Librarians and Library Staff.” American Federation of Teachers. Accessed September 22, 2025. https://www.aft.org/our-members/public-services/librarians-and-library-staff.
5. “Guides and Policies.” Massachusetts Library Staff Association. Accessed September 26, 2025. https://mlsa.ma.aft.org/policies/guides-and-policies.
6. “American Federation Of Teachers 4928 Ma Library Staff Assoc.” ProPublica Nonprofit Explorer. Accessed September 22, 2025. https://projects.propublica.org/nonprofits/organizations/43372803.
7. “Take Action.” Massachusetts Library Staff Association. Accessed September 22, 2025. https://mlsa.ma.aft.org/take-action.
8. “Smears vs. Solutions.” Massachusetts Library Staff Association, 2023. https://mlsa.ma.aft.org/news/smears-vs-solutions-0.
9. “MLSA December 2024 Newsletter.” MLSA, December 2024. https://mailchi.mp/876d80cc0bf5/mlsa_december_2024-newsletter-14205097.
10. “Student Debt Relief Is Union Work!” Massachusetts Library Staff Association, April 8, 2019. https://mlsa.ma.aft.org/student-debt-relief-union-work-0.
11. “Labor Movement Women Send Letter to Biden on ERA.” American Federation of Teachers, December 18, 2024. https://www.aft.org/press-release/labor-movement-women-send-letter-biden-era.
12. Kurtzleben, Danielle. “Biden Says the Equal Rights Amendment Is Law. What Happens next Is Unclear.” NPR, January 17, 2025. https://www.npr.org/2025/01/17/nx-s1-5264378/biden-era-national-archivist-constitution.