Barrie joined The Royal Army Veterinary Corps in 1960 where he attended the War Dog Training School at Melton Mowbray. During his time there his training included, Guard, Security, Red Cross, Mine Detection and Tracker dogs. He quickly established himself as a certificated Dog Trainer. Barrie later took up a position in the Veterinary Hospital as a dresser (now known as a veterinary nurse) at Melton Mowbray, Aldershot and Cyprus. He was later posted to The War Dog Training School in BOAR Germany. Barrie has been training dogs on and off for the last 40 years.
Barrie has acted as Expert Witness in defence of various dogs, accused of being aggressive, as of date all cases defended successfully.