ERLIN is the name for one of the organizational groups, or clusters, of Missouri academic libraries within the larger MOBIUS Library Consortium. MERLIN specifically refers to the four campuses of the University of Missouri system: University of Missouri- Columbia; University of Missouri- Kansas City; University of Missouri- St. Louis; and Missouri University of Science & Technology (formerly University of Missouri- Rolla). The cluster also includes the two law schools and two medical schools in the University system, as well as the State Historical Society and Western Historical Manuscript Collection.

The history of MERLIN dates to the early 1990s. Electronic resource subscriptions often allow for a discount to be applied to purchases made by multiple campuses, and the University of Missouri system organized the consortium to make these purchases. Beginning in 1995, 10 databases were licensed for the UM system under this type of agreement.

When, in the mid-1990s, the MOBIUS Library Consortium formed to create a statewide union catalog system, MERLIN was included as one of the first clusters. At that point, it was given its name, which stands for the Missouri Education and Research Libraries Information Network.

Consortial electronic resource licensing continued. In 2004, the UM Electronic Resouce Initiative received nearly $1 million in an award to expand electronic resources, especially in the field of life sciences. To date, more than 75 electronic resources are purchased by MERLIN for the benefit of University faculty, staff, and students.

These electronic resources represent the research and teaching components of all of the campuses in the MERLIN cluster. These consortial purchases save the University of Missouri millions of dollars in licensing fees each year.
The consortial licensing program is managed by the UM Library Systems Office, a part of the University of Missouri System. The UM Library Systems Office also handles consortial licensing for MIRACL, a consortium that includes all of the MERLIN campuses as well as Saint Louis University and Washington University.