A SAP is a licensed or certified professional (for example a physician, psychologist, social worker, or certified addiction counselor) with DOT-required training (49 CFR 40.281).

After a DOT violation, the employee must see a SAP before returning to safety-sensitive work. The SAP:

• Evaluates the employee and recommends education and/or treatment.
• Conducts a follow-up evaluation to confirm the employee complied.
• Sets the follow-up testing plan the employer must carry out.

The SAP works for the safety of the public, not as the employee's advocate. The employer must give an employee with a violation a list of qualified SAPs (49 CFR 40.287).