North turned professional in 1972. He had a moderately successful career on the PGA Tour made remarkable by the fact that two of his three wins on the Tour were in the U.S. Open. The first PGA Tour win of North's career came at the 1977 American Express Westchester Classic. He was 28 years old when he won the 1978 U.S. Open at Cherry Hills Country Club in Cherry Hills Village, Colorado. He moved into the lead after the second round, and was one shot ahead going into Sunday, but an erratic final round left him needing to make a five on the last hole to take the championship. He struggled up the 18th, finding the rough twice and then landing in a greenside bunker, but he made a four-foot putt to win by one stroke over J. C. Snead and Dave Stockton.