Ellis Leonard received his DVM degree in 1934 from the New York State College of Veterinary Medicine at Cornell University. Following graduation he worked at Kansas State University and then opened a private practice in New Jersey. In 1948 he returned to Cornell to as director of the Small Animal Clinic and remained in that position until his retirement in 1969.
Dr. Leonard is well known for his small animal work, but he is also recognized for his research and writing about the history of Cornell's veterinary college, the New York State Veterinary Medical Society, and veterinary medicine in general. After his retirement he published three books and and several articles on these topics.
Dr. Leonard died February 7, 1991 at the age of 86.