To add new users to the workspace you need to be an Admin or an Owner of this workspace. You can see your role under the workspace name in the list of the workspaces.
To add a new user click on the "Add New User" button, and the popup window will appear. In there, you can enter the email of the person you want to add. You can batch-add users, just enter the emails, separating them with spaces, commas, semicolons, or tabs. Or just enter them one by one, pressing enter after each one.
Chose the role for this person: Designer, Viewer, Commentator, or Admin. To add a user to the workspace, they already need to have a Sympli Versions account. If they don't, the Owner will get the notification saying that the user with such email doesn't exist. Please make sure the user has a Sympli Versions account.
If you want the user to be in charge of billing and be able to manage seats in your Workspace's subscription - check the box "This user is Accountant". Then click "Add User" and it's done, the user is now a part of this workspace.
You can also disable the user, edit his role and access, and remove the user from the workspace. Just find a user you want to manage and hover with your pointer - the options will appear to the right of the user's name.
When you disable a user, they will lose access to the projects in this workspace, and therefore lose a seat. This means you can assign this seat to someone else. If you want to bring this user back - just reactive them from this page, you will not need to enter their email again.