You can invite existing members or invite by email.
When you invite people, the invitees have the option of deciding if they want to join the space or not. Before they gain access to the space, they must accept the invitation.
When you invite existing members, they will receive an invitation to join this space in their notifications and by email. When you invite people by email address, they will receive an email with instructions on how they can set up their account and join this space.
is requesting access to a wiki that you have locked: http://my.axerosolutions.com/spaces/5/communifire-documentation/wiki/view/21782/manage-space-invite-people