In 1964, New was appointed Chief of Pediatric Endocrinology at Cornell University Medical College, a position she held for 40 years. In 1978, she was named Harold and Percy Uris Professor of Pediatric Endocrinology and Metabolism. In 1980, New was appointed Chairman of the Department of Pediatrics at Cornell University Medical College and Pediatrician-in-Chief of the Department of Pediatrics at New York-Presbyterian Hospital.