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Find an overview of GreenGlass for Groups.

About GreenGlass for groups

GreenGlass group functionality is an extension of standard GreenGlass designed to support shared print projects focused on monographs. GreenGlass group functionality makes it possible for you to understand your shared collection and your place in it.

You can use GreenGlass group functionality to help you visualize your shared collection with respect to attributes such as geography, size, overlap, age, subject dispersion, and usage. This information will help you take full advantage of the GreenGlass Model Builder.

In the Model Builder, you can experiment with a number of retention scenarios and immediately see the impact on each library in your group. Various title attributes can be invoked and specific thresholds can be set in real-time. You can use Model Builder to build models for the entire group or for any number of group library subsets. Models are easily saved and compared.

Model Builder provides a holistic view of your options and dependencies, allowing you to engage in fact-based conversations about cost-effective shared print strategies.

Once your group has finalized its shared print agreement, SCS allocates retention commitments to each library, creating a safety net for each title. This makes it possible for all libraries in the group to protect the right books and share responsibility for the collective collection.


The trajectory and timeline of your shared-print project will be distinct and will depend on the size, scope, goals, and urgency of your participant libraries. However, there are five basic components or phases for all shared-print projects:

  1. Project management and governance
  2. Key project decisions (scope/comparators/special categories/schedule)
  3. Retention models
  4. Retention allocation
  5. Retention disclosure

Title-sets and title-holdings

In the context of a shared print project, the word "title" can mean two very different things. The following terms help avoid confusion:

  • Title-set
  • Title-holding

Title-sets and title-holdings are used to build models in the GreenGlass Model Builder. Once a group has agreed on a suitable model, SCS will assign specific titles to each library for retention. Final retention allocations are made at the item level. Items flagged for retention will be identifiable and retrievable on the individual library side of GreenGlass.


Title-set is used to describe all the holdings of a particular title. Any given title-set could have one or more than one associated title-holding.

Title-set attributes provide context for the characteristics of the shared collection and are the primary building blocks in the GreenGlass Model Builder. They are defined on the Group Visualization pages in GreenGlass (GROUP Collection > Visualize) and include:

  • Aggregate uses
  • Last charge year
  • Publication year
  • Last item add year
  • HathiTrust


Title-holding is used to describe the related thing that is owned by one library in the group. A library's title-holding is typically represented in the local OPAC by a single bibliographic record.

The title-holding is a unit of measure in the GreenGlass Model Builder. Retention estimates are stated as the number of holdings for each library that meet the title-set parameters of a given model.

Since the SCS environment is focused exclusively on monographs, a title-holding usually has one associated item. In the case of duplicate copies or multi-volume sets, however, a single title-holding can have more than one associated item or volume on the shelf. On average, an SCS library can expect to have 10% more items than holdings.