To apply for membership in the American Association for Thoracic Surgery, an Active or Senior member, who agrees to act as the primary sponsor, must initiate the application by entering the Members Only area. The membership candidate will then be provided with a login and instructions to access the online application. The completed application form will be distributed to three sponsors who are Senior, Active, or Honorary members of the Association.  These three sponsors are required to forward letters of recommendation on behalf of the applicant.  Current members of the Membership Committee may not act as sponsors.