CW MARS Libraries Connecting Communities Logo


is a diverse multi-type library consortium made up of over 100 member libraries primarily located in Central and Western Massachusetts. CW MARS is an acronym that stands for Central and Western Massachusetts Automated Resource Sharing.

We are the largest of nine library consortia in Massachusetts. Our membership is made up of academic, public, and special libraries of all sizes, from tiny towns with populations under 500 to large urban libraries with many branches. CW MARS hosts and supports the hardware and software needed to power our shared online library catalog and library staff software. We provide technical support to member libraries.

At a Glance


waiting to be enjoyed in our shared catalog.


borrowed in 2023, including 9.4 million physical items & 2.4 million e-items


with 190 branch locations across Central and Western Massachusetts


registered in our shared system

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CW MARS Policies



CW MARS empowers member libraries to provide excellent services to their communities through resource sharing technology.


CW MARS is a visible leader for its member libraries, connecting communities in Central and Western Massachusetts, and advocating for library funding.


CW MARS upholds the following core values:

  • Equity, Diversity, and Inclusion
  • Open Access
  • Privacy and Security
  • Respect, Cooperation, and Mutual Trust
  • Innovation
  • Lifelong Learning
  • Cost-Conscious Economic
  • Sustainability

CW MARS is primarily funded through annual membership fees and also receives significant support from the Massachusetts Board of Library Commissioners (MBLC).

Additional funding for telecommunications comes from the Federal Communications Commission (FCC) E-rate program.


The governing body of CW MARS is Users Council, which is made up of all member libraries. The Users Council meets at least four times a year, and each member library has one vote.

The CW MARS Executive Board is made up of 12 voting members of the Users Council. The Executive Board meets monthly. Directors are elected annually and serve for two year terms.


C/W MARS was formed to administer and utilize technology to promote sharing between libraries.

The idea for C/W MARS began in 1978, when 28 librarians in central and western Massachusetts joined together to investigate the possibility of cooperative automation for purposes of resource sharing, circulation control, and improved public access to resources in general. With the support of their Regional Library Systems, they applied for and won an LSTA grant and hired a consultant to do a feasibility study. The final report, issued in 1981, recommended an integrated, shared online system as both achievable and desirable in terms of cost, benefits, and services. A subsequent LSTA grant was awarded to fund central site hardware and software. An RFP was issued in September of 1981 and C/W MARS was established.

Representatives of the 28 member libraries painstakingly evaluated vendor capabilities and performance for circulation, interlibrary loan, acquisitions, cataloging, bibliographic record management, hardware and software. DataPhase Systems was chosen because it most closely met the requirements of C/W MARS members, and a contract was signed in September of 1982. The first remote bibliographic conversion sites were operational in October of 1983.

On July 27, 1984, C/W MARS became an independent non-profit organization incorporated under the Internal Revenue Code 501(c) and Chapter 180 of Massachusetts State Law.

In December of 1985, Utlas International purchased the local system software from DataPhase. Six year later, with the demise of Utlas International, C/W MARS signed a contract with CARL Systems on May 1, 1991, to provide new software on the existing hardware. The transition to the new CARL system took place over Columbus Day weekend in 1992.

In December of 1998 C/W MARS signed a contract with Innovative Interfaces, Inc to migrate from CARL to Millennium ILS.

Concerned about rising costs and wanting more control over software improvements, in the fall of 2010 C/W MARS began the process to migrate to an open source integrated library system, Evergreen. In May of 2012, C/W MARS went live on Evergreen.

In FY2021 CW MARS has grown to 150 member libraries and 175 outlets (branch locations).

Employment Opportunities

CW MARS Open Positions

There are no open positions at this time.

Request for Proposals


There are no open RFPs at this time.

Become a Member Library

Become a Member Library

Why be Part of CW MARS?

Libraries interested in CW MARS membership are encouraged to read through our list of member benefits and membership requirements.

Membership Requirements

Membership is open to libraries and other non-profit organizations that are

  • members of the Massachusetts Library System (MLS)
  • governed by a single legal entity that has full administrative and fiscal responsibility for daily operations

Member Libraries must make all circulating collections available to all members of the consortia.

Membership Benefits

Member Library Benefits

  • shared integrated library system (ILS)
  • cataloging services and support
  • ILS technical support and training
  • custom reports
  • annual statistics
  • access to consortia-wide subscriptions
    • OverDrive econtent
    • NoveList readers advisory database
    • NoveList online catalog record enhancements
    • Book cover images subscription
    • computer/room reservation software
  • CW MARS applies for grants to keep membership affordable
  • CW MARS negotiates group buying discounts

Benefits for Your Patrons

  • access to millions of items in shared catalog
  • access to thousands of ebooks, audiobooks, magazines and video via consortial OverDrive digital collection
  • holds priority on CW MARS OverDrive collection
  • easily place holds on materials via online catalog
  • pick up requested items at your library
  • use CW MARS library card at any CW MARS member library
  • ecommerce platform for online payments of fines and charges
  • My Account allows patrons to manage notification settings, profile details, place holds, renew items, and pay fines/charges online
  • Mobile apps for Catalog and OverDrive

Optional Member Serivces

  • Internet line and telecommunication hardware
  • technical support for networked libraries
  • wireless access, reporting and support
  • email and productivity tools
  • print management software including mobile print option
  • PC Desktop support