His father was born in Bessarabia. Ernest M. Gruenberg was born in New York City. He received his A.B. in 1937 from Swarthmore College and his M.D. in 1941 from the Johns Hopkins University School of Medicine. He served in the United States Army during World War II, spending seven months as a prisoner of war after the invasion of Normandy. After the war, Gruenberg was an assistant in the department of psychiatry and mental hygiene at Yale University, where he later earned additional graduate degrees in public health. From 1949 to 1954, Gruenberg was the executive director of the New York State Mental Health Commission. During the late 1950s, he was on the staff of the Milbank Memorial Fund and served with the New York State Psychiatric Institute. Gruenberg thenjoinedthefacultyof the Collegeof Physiciansand Surgeons at Columbia University and held that post until 1975, achieving the rank of professor. He then came to the Johns Hopkins University, where he was professor and chairman of the department of mental hygiene in the school of hygiene and public health until his retirement in 1981. He held a joint appointment in psychiatry in the school of medicine. Gruenberg distinguished himself as a mental health epidemiologist and a pioneer in community mental health.