If you have editor or higher permission to Box content, you are able to add external collaborators (with the exception of Level 1 files and folders). Simply type in the full email address in the collaboration screen, select the appropriate permission level, add a message if you wish, and click send.
Important Note: External collaborators must enroll in 2FA with Box to access Chico's shared content. Box provides directions to the user when a collaboration invite is sent. If you would like to view setup instructions for external collaborators, click here.