There are approximately 1,500 members of THIMA. These HIM professionals work in all levels of health care settings, health maintenance organizations, insurance companies, law firms, and information systems companies.

The majority of THIMA members are Registered Health Information Administrators (RHIA) or Registered Health Information Technicians (RHIT). RHIAs are managers as well as information specialists. Individuals who earn a bachelor's degree from an accredited college program are entitled to sit for a certification exam. RHITs are skilled in analyzing health information. Successful completion of an associate's degree from an accredited college program or the AHIMA Independent Study Program qualifies one to sit for the RHIT credentialing examination. Other active members of THIMA are individuals who are Certified Coding Specialists and those who are Certified in Healthcare Privacy (CHP) and/or Security (CHS). Anyone interested in the activities of the Association may join as an associate member.

Benefits of membership in THIMA include member rates at all educational programs, an electronic newsletter, and the member rate for a comprehensive legal handbook which is published annually. THIMA holds two membership meetings each year, the Annual Meeting and the Fall Meeting held in conjunction with the Tennessee Hospital Association. Several educational workshops are held each year.

According to the Bureau of Labor Statistics, employment of HIM professionals is expected to grow much faster than the average for all occupations through 2008.