Few players in NHL history have produced as consistently as Federko, the first player in League history to have at least 50 assists in 10 consecutive seasons.

The St. Louis Blues selected Federko, a high-scoring center, with the No. 7 pick in the 1976 NHL Draft after he had 187 points (72 goals, 115 assists) in 72 games for Saskatoon of the Western Hockey League, breaking the WHL single-season scoring record held by Bobby Clarke. The Blues sent Federko to Kansas City of the Central Hockey League but brought him to St. Louis after he had 69 points (30 goals, 39 assists) in 42 games.

Federko's breakout season was in 1978-79; he finished eighth in the NHL in scoring with 95 points (31 goals, 64 assists). His first of four 100-point seasons came in 1980-81, when he finished with 104 points (31 goal, 73 assists) to help the Blues set then-team records with 45 wins and 107 points. He led the Blues in scoring nine times, including eight in a row from 1978-79 through 1985-86. Federko and the Blues came within one victory of advancing to the Stanley Cup Final in 1986 before losing to the Calgary Flames, and despite playing only three rounds, he tied teammate Doug Gilmour for the most points (21) in the 1986 playoffs.

On March 19, 1988, Federko had an assist to become the 22nd player in NHL history to have 1,000 points. He spent 1988-89, the last of his 13 seasons with the Blues, as captain. Federko averaged more than a point a game in each of his last 11 seasons with St. Louis.

Federko's time with the Blues ended when he was traded to the Detroit Red Wings on June 15, 1989. He played one season with the Red Wings, finishing with 57 points (17 goals, 40 assists) in 73 games before announcing his retirement. His final regular-season game on April 1, 1990, was the 1,000th of his NHL career. He finished with 1,130 points (369 goals, 761 assists).

The Blues retired his No. 24 on March 16, 1991, and Federko was inducted into the Hockey Hall of Fame in 2002, becoming the first player inducted into the Hall primarily for his accomplishments with the Blues. He also has spent more than 20 years as an analyst and studio host on Blues telecasts.