A Group Membership is any membership that contains multiple constituents connected under the same transaction and membership level, such as a corporate or family membership. In the setup of any Membership Level, you can set how many Primary and Secondary members can be included on a Membership Level. You can also customize the labels for Primary and Secondary members. When filling out the membership registration form, the registrant will enter names and contact information for all the constituents who will be grouped under one membership.

You can read more about the different types of memberships available in this article: https://support.donorview.com/en/support/solutions/articles/9000211023-what-types-of-memberships-can-i-create-