Zephyr comes with 4 default Roles and more can be added to the system:

Default Roles (Test Manager, Lead, Tester, Defect User)
There are 4 roles that are defaults: Test Manager, Test Lead, Tester and Defect User. The first 3 can be added in the Test Manager's Desktop via the Resource Management application. Once the user has been added to the system, they need to be assigned to a project. They will get an email with login details that they can use to access their Zephyr Desktop.

The fourth role (Defect User) which are users of the Internal Defect Tracking System, can be added in the Test Manager's Desktop via the Users tab of the Defect Admin application.
Custom Roles
Additional roles can be created in the Customizations tab of the Administration application and the users with those roles can be added in the Resource Management application. Once the user has been added to the system, they need to be assigned to a project. They will get an email with login details that they can use to access their Zephyr Desktop.

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