An operator can only belong to one Workgroup, but they can be the Manager or Authorized Manager of multiple Workgroups.

The explanation for this behavior is as follows:
Software evolves organically, and it was only in the last few years that business use cases started coming in arguing for operators to belong to more than one workgroup at a time.  We've started down that path in v7, changing the "Contacts" list in Data-Admin-WorkGroup to "Authorized managers".  The Case Manager portal knows to browse the list of workgroups that the current user is an authorized manager for, and displays workbaskets associated with each of these workgroups.
 

Hi Deb,

Following is some detailed documentation on Work Groups, which may help to answer your question.

A work group is a combination of a supervisor and an associated WorkBasket. Work groups may be used for authorization checks against individual attachments if enabled by AttachmentCategory rules.

A work group is an instance of the Data-Admin-WorkGroup class. It is accessed on the Rules By Type Explorer in the Organization category.

An operator’s work group is displayed on the Operator ID rule form on the Work Settings tab.

A work group consists of a single supervisor and one Workbasket.

An operator, and thus a supervisor, may be a member of only one work group on the operator ID rule form; a work basket may also belong to only one work group on the workbasket rule form.

Note: Multiple Work Groups may be created with the same supervisor and/or workbasket. The Work Group rule form does not validate whether the supervisor or workbasket is already used by another Work Group, nor does the rule form validate whether the supervisor’s operator ID record lists that Work Group.

The Work Group is unrelated to Access Groups and Roles and does not change if the operator switches Access Groups or Applications. Work Groups are independent of whatever application the operator is currently running.

Thanks,

Gisela