Using the functional medicine rubric in physical medicine and rehabilitation (PM&R), a physiatrist can capitalize on addressing the root causes and downstream effects in patients with chronic diseases. Similar to the International Classification of Function model in rehabilitation, the functional medicine model uses biopsychosocial understanding with a systems biology approach to find fulcrum points to create the biggest impact on health care. Given the position of rehabilitation medicine with the type and location of patients, both functional medicine and PM&R would benefit from a mutual partnership.