The U.S. Constitution
(Article II, Section 2) provides for "executive departments" that answer (in writing) to the President. The chief executives (Secretaries) of these 15 departments, plus the Vice President and a handful of miscellaneous officials, compose the President's "Cabinet". The Cabinet Secretaries correspond roughly to Minister
s under other government structures.
Special thanks to the "President Bush's Cabinet" page at http://www.whitehouse.gov/government/cabinet.html