Cambridge COunseling Associates

Our Staff

L. Curtis Wittmann, M.D.
​Dr. Wittmann is a licensed Board Certified Psychiatrist who received his M.D. at Washington University in St. Louis. He completed his residency training at the Massachusetts General Hospital (MGH)/McLean Hospital combined program. He served as the MGH Administrative Chief Resident and the MGH Consultation-Liaison Chief Resident during his training. Dr. Wittmann maintains a private practice in Cambridge and provides psychopharmacology, psychotherapy, combined treatment, and consultation. He is an instructor in psychiatry at Harvard Medical School and works in the MGH Bipolar Clinic and Research Program and the psychiatric emergency department at MGH. His clinical specialization includes mood and anxiety disorders as well as co-occurring medical and psychiatric illnesses.

George (Djordje) N. Koldzic, M.D. 
Dr. Koldzic is a Board Certified Psychiatrist with special interest in psychiatric care of patients with mood and anxiety disorders. He is a graduate of the General Psychiatry Residency Training Program at Tufts Medical Center in Boston and completed an Adams House fellowship in psychodynamic psychotherapy through the Brigham and Women’s Hospital/Faulkner Hospital Department of Psychiatry. Dr. Koldzic graduated from the Belgrade University School of Medicine, Belgrade, Serbia. He completed his post-graduate training in neurology and neuro-immunology at University Hospitals in Belgrade, Serbia and served as a post-doctoral research fellow in psychoneuroimmunology at Brigham and Women’s Hospital and UMass Medical Center. During his training and subsequent clinical practice in psychiatry, he received multiple teaching and exceptional practice awards. Dr. Koldzic is currently an assistant professor in psychiatry with Tufts School of Medicine. His clinical affiliation is through Tufts Medical Center’s Department of Ambulatory Psychiatry.

John T. Chirban, Ph.D., Th.D.
Dr. Chirban is a licensed psychologist in Massachusetts and California (Ph.D., Boston University, University Professors program in Clinical Psychology and Oral Histories; Th.D., Harvard University in Medicine, Psychology, and Religion) as a Certified Health Provider with more than 25 years of clinical experience as the Director of Cambridge Counseling Associates. He teaches and specializes in the areas of intimacy and sexuality, sexual dysfunction, family relationships, and spirituality and psychotherapy and has taught at The Cambridge Health Alliance at Harvard Medical School for more than 30 years. Areas of his clinical interest include identity, relationship and family issues, personality problems, health concerns, and issues of meaning. Please see Additionally, he has served as a Guardian ad litem for the family court systems. Dr. Chirban has authored numerous book and professional articles, and has written two weekly blogs for Psychology Today, having served on the Advisory Board of the Dr. Phil show since its inception.