Bill Barber's sheer physical strength was one of his most important attributes. In junior, he centered a top scoring line with Jerry Byers and Al Blanchard in Kitchener. All three were drafted high in the 1972 Amateur Draft. Barber was selected seventh overall by Philadelphia and was the only one of the three who went on to make a significant impact in the NHL.
Initially he was assigned to Richmond of the AHL by the Flyers, but after just 11 games he was recalled when Bill Flett sprained his knee. Barber was among the top rookies all year, finishing the season with 30 goals and 34 assists, making him a contendor for the Calder Trophy for Rookie of the Year. Part of his immediate success was in coach Shero's decision to play Barber as a left wing to Bobby Clarke on the first line rather than keep him at his natural center position on a fourth line. Clarke quickly realized Barber had an excellent shot and good hands and endeavored to get the puck to the port side whenever possible. He scored 34 goals in each of the next two years, winning the Stanley Cup in 1974 and 75. Barber had a career year in 1975-76 by scoring 50 and getting 112 total points.
Barber had four more 40-goal seasons during his career, but the continuing deterioration of his left knee forced him to retire, and he was unable to finish the 1983-84 season. He first injured the knee crashing into the boards while back checking in December 1982 in Pittsburgh. He recovered after missing a few games, but the same knee gave out on him again later in the season. By the spring he required surgery, and once the knee was opened doctors discovered massive damage to the joints and cartilage that had been masked for years by strong muscle mass around the bone. It was completely reconstructed and he missed the entire 1984-85 season trying to recover. After the year was over, he knew his knee would not be strong enough to endure the physical demands of the NHL. He went into coaching, starting with the Flyers farm team and assuming head coaching of the NHL team during the 2000-01 season.
He finished his career with 420 goals and was inducted into the Hockey Hall of Fame in 1990, one of only three players from those Flyers teams - Bernie Parent and Bobby Clarke were the others.