Dr. Kirk is the Toni and Timothy P. Hartman Distinguished Teaching Professor in Internal Medicine at the University of Texas Southwestern Medical Center. She is a general internist and geriatrician. Dr. Kirk attended the University of Nebraska Medical College and trained in internal medicine at University Hospital in Boston.  She has practiced general internal medicine and geriatrics at UT Southwestern for over thirty year in the general internal medicine clinic, the Parkland Center for Internal Medicine, and the Parkland Geriatrics Clinic.  She attends on the Eisenberg geriatrics service at Clements University Hospital.

She is President-Emeritus of the American College of Physicians. She has published on medical professionalism, faculty development, clinical guidelines, and patient education.  She is on the Council on Medical Education of the American Medical Association and the Board of Directors of the Accreditation Council for Graduate Medical Education.   She is an Associate Program Director in the internal medicine residency training program at UT Southwestern and had previously served as the Associate Dean for Graduate Medical Education.