Greenwich Hospital has announced that Trumbull resident Marc Kosak has been appointed as the new chief operating officer, effective Saturday, Oct. 3

Kosak has worked at Greenwich Hospital since 2004. Prior to his new appointment as chief operating officer, Kosak served as senior vice president of Operations at Greenwich Hospital since 2015. Kosak has also served as the vice president of Administration and prior to that the administrative director of Physical Medicine.

Prior to joining Greenwich Hospital, Kosak spent 10 years working for Burke Rehabilitation Hospital in a variety of positions with increasing responsibility. He is a Fellow of the American College of Healthcare Executives.