Dr. MacNamara completed his undergraduate degree and DVM at Cornell University. He began his career in mixed practice seeing horses and small animals. He went on to work for Dr. Peter Casadei at Roosevelt Raceway for several years and afterwards started his own practice in Goshen, NY, where he practiced at The Meadowlands, Monticello and Yonkers Raceway as well as local farms and training centers He became the lead veterinarian for the Equine Referral Hospital at the Meadowlands Racetrack in 2002 and saw surgical and medical cases there until the track backstretch was closed down in 2015. He has held academic positions at New Bolton Center and the City University of New York. Currently, he runs Warwick Equine Clinic providing general and emergency medical and surgical care for local clients.
He has competed in eventing, show jumping and as a Standardbred racehorse trainer and driver. His wife, Laura, is a dressage/combined training instructor and helps with in patient care and surgery. They live in Warwick with their two sons, four dogs, three horses, 4 cats and a macaw.