In the Corporate portal, under Organization > Users & Permissions, you find the three tabs Users, Grouping and Permissions. How the whole Organization area is structured is described in Organization: Business Units, companies and users.
Users
The Users tab lists all users of your company with name, Company, email and creation date. Filters (e.g. email address, first name, last name) help you find individual users quickly and edit them.
Groups (Grouping)
Groups bundle users, e.g. all admins or all employees of a department. Each group belongs to a Business Unit. Via Create New you create a new group: you give it a name, choose the Business Unit and define the members via filters, e.g. by email addresses or names. Users matching the filters are added to the group automatically.
Groups are the target of assignments in many places: for example, you can assign a payment method (see Corporate payment methods) or a Limit Policy (see Policies: Limit Policies (Beta) and Terms & Conditions) specifically to a group.
Permissions
Permissions control who can see and change what in the portal. A permission applies to a Business Unit and is assigned to a group or an individual user (Access Name).
Via Create New you open the permission matrix. For each resource you choose Read, Write or Admin. Resources include Users, Transactions, Companies, Configs, Widgets, Payment Method, Auth Config, Permissions, Profile Providers, Groups, Report Configs and Business Units.
Important: A group alone does not grant any rights. Only the permission defines what its members can access. For administrators we recommend a dedicated admin group with a matching permission.
Note: Users who are not part of a managed Business Unit can add some roles themselves via their profile menu. In managed Business Units, admins control access via groups and permissions. How your company takes over its Business Unit centrally is described in Central onboarding: rolling out 1-CP in your company.