You can view all members in your workspace and invite new members from the Workspace Members page. When you click on your profile image at the top right, you'll see a revealed window where your workspace(s) are listed—select a workspace to go to its Workspace Members page.

On this page, you can add more members by clicking on the "Invite Member" button; you can assign roles and set their access level while inviting them.

Once you invite them, they will receive an email letting them know that they were invited, and they'll need to register to Zeplin through this email if they have not done so yet.

Keep in mind that you can invite more members with paid roles than the number of seats you've paid for in your workspace. When this happens, Zeplin will apply a 7-day grace period where you can either confirm or revert the changes. Learn more about the grace period here.

When you upgrade to the Advanced, Team or Organization plan from the Free, Basic, or deprecated Starter or Growing Business plans, you will become the Owner of a new workspace, and all of your existing project members will be added to your workspace as a Reviewer with restricted access. This means they can only access projects and styleguides they have been invited to, and they can only view screens and add comments without accessing technical details—you can change their roles and access levels anytime from the Workspace Members page.

If you create a workspace from scratch, you, as the Owner, will be the only member shown in your member list first, and you'll need to add your teammates to collaborate.

Workspace members can have four different paid roles that require seats: Owner, Admin, Editor, and Developer (available on Advanced, Organization, and Enterprise plans). You can also assign your members the Reviewer role, which is free of charge and does not count as a paid seat.

You can learn more about the details of each role from this article, and how to manage their access levels here.