Rivers was a McDonald’s All-American for Proviso East High School in the Chicago metropolitan area. Rivers represented the United States with the national team in the 1982 FIBA World Championship, in which he led the team to the silver medal, despite missing the last shot in the final, which could have given the title to his team. After his third season at Marquette University, Rivers was drafted in the second round (31st overall) of the 1983 NBA draft by the Atlanta Hawks. He graduated from Marquette while completing course work as an NBA player. He spent the next seven seasons as a starter in Atlanta, assisting star Dominique Wilkins as the team found great regular season success. He averaged a double-double for the 1986–87 season with 12.8 points and 10.0 assists per game. Rivers later spent one year as a starter for the Los Angeles Clippers and two more for the New York Knicks, before finishing his career as a player for the San Antonio Spurs from 1994 to 1996.

Rivers began his coaching career with the Orlando Magic in 1999, where he coached for more than four NBA seasons. Rivers won the Coach of the Year award in 2000 after his first year with the Magic. That season, he led the team that was picked to finish last in the league to a near playoff berth.

He made the postseason in his next three years as coach, but was fired in 2003 after a 1–10 start to the season.

After spending a year working as a commentator for the NBA on ABC (calling the 2004 Finals with Al Michaels), he was hired by the Boston Celtics as their head coach in 2004. During his first years with the Celtics, he was criticized by many in the media for his coaching style, most vociferously by Bill Simmons, who in 2006 publicly called for Rivers to be fired in his columns.

As a result of the Celtics’ 109–93 victory over the New York Knicks on January 21, 2008, Rivers, as the coach of the team with the best winning percentage in the Eastern Conference, earned the honor to coach the East for the 2008 NBA All-Star Game in New Orleans. On June 17, 2008, Rivers won his first NBA Championship as a head coach after defeating the Los Angeles Lakers in six games. The Celtics needed an NBA record 26 postseason games to win it. Rivers played for the team that held the previous record for most games played in a single postseason: the 1994 New York Knicks played 25 postseason games.

On May 13, 2011, after months of rumors that he would retire, ESPN reported that the Celtics and Rivers agreed upon a 5-year contract extension worth $35 million.

On February 6, 2013, Rivers notched his 400th win with the Celtics in a 99–95 victory over the Toronto Raptors.

On June 25, 2013, the Los Angeles Clippers acquired Rivers from the Celtics for an unprotected 2015 NBA first round draft pick. He also became the senior vice president of basketball operations on the team. In his first season as their head coach, Rivers led the Clippers to a franchise-record 57 wins, garnering the 3rd seed in the Western conference. The 2014 NBA playoffs first round playoff series against the Golden State Warriors was marred when TMZ released an audiotape containing racially insensitive remarks made by the then-Clippers owner Donald Sterling. Though there was a possibility of the Clippers boycotting the series, they would play on, holding a silent protest by leaving their shooting jerseys at center court and obscuring the Clippers logo on their warm-up shirts. Rivers himself stated that he would not return to the Clippers if Sterling remained as owner the following season. NBA commissioner Adam Silver responded to the controversy by banning Sterling for life and compelling him to sell the team. After the team was sold to Microsoft CEO Steve Ballmer for $2 billion on August 12, 2014, Rivers remained with the Clippers.

On June 16, 2014, the Clippers promoted Rivers to president of basketball operations in conjunction with his continuing head coaching duties. Although Dave Wohl was hired as general manager, Rivers had the final say in basketball matters. On August 27, 2014, he signed a new five-year contract with the Clippers.

On January 16, 2015, Rivers became the first NBA coach to coach his own son, Austin Rivers, until June 26, 2018, when he was traded to the Washington Wizards for Marcin Gortat.

On August 4, 2017, Rivers gave up his post as president of basketball operations. However, he continued to split responsibility for basketball matters with executive vice president of basketball operations Lawrence Frank. On May 23, 2018, Rivers and the Clippers agreed to a contract extension.

On May 31, 2019, Rivers made comments on Kawhi Leonard during an appearance on ESPN, stating that “He is the most like Jordan that we’ve seen”. The Clippers were fined $50,000 due to Rivers’ comments in violation of the league’s anti-tampering rule.

In the 2019–20 season, Rivers earned his 900th win as a head coach after the Clippers won at home against the Portland Trail Blazers on November 8, 2019. In the Western Conference seminfinals, the Clippers jumped to a 3–1 lead before losing 4–3 to the Denver Nuggets. Rivers became the first coach in NBA history with three teams who failed to advance from a best-of-seven series after taking a 3–1 lead. He had previously been the only coach in NBA history whose teams had twice failed to advance from a best of seven series after taking a 3–1 lead.

On September 28, 2020, Rivers stepped down following the Clippers’ defeat to the Denver Nuggets in the conference semifinals. His record through seven seasons with the team was 356-208, but he was ultimately unable to lead the Clippers to their first conference finals appearance in franchise history.

On October 3, 2020, the Philadelphia 76ers announced that they had hired Rivers as their head coach.