HIMS stands for Human Intervention Motivation Study and formed in a partnership with ALPA (the Airline Pilots Association) and the FAA in the 1970s. The goal of the original study was to collect data in a program that allowed pilots with alcohol problems to get help and with the possibility (but not guarantee) of preserving a career if conforming to program guidelines. Congressional authorization and appropriation allow the FAA to gather data about the program and offer a partnership between the pilot, the company, the union, and the FAA to identify what a commercial pilot should do to return to cockpit after getting treatment for an alcohol problem.
The FAA does not administer the HIMS program. Each airline operating a HIMS program designs to their need but there is collaboration in the industry. HIMS programs, individually administered at the airlines, contain similar elements in promoting an effective recovery process for the pilot. On the other hand, not every airline has a designated HIMS program, but even in those cases, an individual program can be designed. It just takes some extra work.