Gallagher was a nine-time U.S. Champion and finished 19th at the 1968 Holmenkollen Ski Festival in the 50 km event.

[1] Gallagher was introducing to skiing by his father, a veteran of the 10th Mountain Division, and in 1959 won the U.S. junior cross-country championships.

He later attended the University of Colorado, and earned a bachelor's degree from Castleton State College in 1967.

At Castleton, besides skiing he competed in cycling and middle-distance running, setting a New England collegiate records over 880 yards, one mile and 2-miles.

[1] After retiring from competitions, Gallagher coached the U.S. National team and was part of the 1980, 1984, and 1992 Olympic cycles.