If you want to invite someone to a single project (without giving them access to your organization), see the Collaboration page.

How to invite to an organization?
1
Click on the Invite button
From the sidebar, go to Organization, then click Members, and use the Invite button.
2
Enter the email
Add one or more email addresses of the people you want to invite.
3
Select a role
Choose between Member, Admin, or Owner.
For details on what each role can do, see the Members page.
4
Send the invite
Click Invite. The person becomes a member once they accept.
Managing invites
- Pending invites: Resend or revoke them from the Members page.
- Accepted invites: Change a person’s role at any time.
- Remove access: Remove members who no longer need access.