The ABAI is a Conjoint Board of its two parent boards:
A Conjoint Board is a body established under the joint sponsorship of not less than two Primary Boards. The ABAI is sponsored by the American Board of Internal Medicine and the American Board of Pediatrics. Its purpose is to set training standards and evaluate competence of individual candidates in an area of specialty practice common to the sponsoring groups.
A Conjoint Board resembles a Primary Board in that it is separately incorporated and has similar responsibility for determination of requirements for certification, accepting candidates for certification, administering examinations, and issuing certificates. It differs from a Primary Board in that it is established and functions under the joint sponsorship of not less that two Primary Boards. Its members are appointed by some or all of the respective sponsors and approved by the sponsoring Primary Boards, its policies are determined in conformity with the policies jointly established by the sponsoring boards, and it may or may not be financially independent.
Applicants for certification must complete satisfactorily a preliminary training program acceptable to at least one of the sponsoring boards and to the Conjoint Board in order to be considered for examination by the Conjoint Board.