He played collegiately for UCLA Bruins and professionally in the National Basketball Association (NBA) for the Portland Trail Blazers, San Diego / Los Angeles Clippers, and Boston Celtics.

The 6-foot-11-inch (2.11 m) Walton won three consecutive national college player of the year awards (1972–1974), while leading UCLA to NCAA championships in 1972 and 1973 and an 88-game winning streak.

[6][7] After retiring from the NBA, Walton overcame stuttering and embarked on a second career as a sportscaster, working both as a studio analyst and color commentator with several networks and teams.

"Yes," said Gloria Walton, "then when the referee wasn't looking, Bruce would give the player an elbow and let him know that the skinny guy was his kid brother.

"[13] Walton's struggle with injury and pain began while at Helix, where he broke an ankle, a leg, several bones in his feet, and underwent knee surgery.

"They had some great teams with Elvin Hayes and Calvin Murphy and future head coaches and broadcasters such as Pat Riley, Rick Adelman, Rudy Tomjanovich, Jim Barnett, and Stu Lantz.

It was a humbling honor and privilege to be on the same squad as true legends Monroe Nash, Wilbur Strong, Phil Edwards, and Bruce Menser.

With Walton playing alongside Henry Bibby, Larry Farmer, Wilkes, Lee, and Swen Nater, UCLA finished 14–0 in the Pac 8 Conference.

He was named first-team All-American with Jim Chones of Marquette, Bo Lamar of the Louisiana-Lafayette, Ed Ratleff of Long Beach State, and Tom Riker of South Carolina.

"[41] UCLA finished 26–4 and 12–2 in the Pac 8 Conference, with Walton playing alongside Keith Wilkes, David Myers, and Marques Johnson.

[43] He was named 1st Team All-American alongside Marvin Barnes of Providence, John Shumate of Notre Dame, David Thompson of North Carolina State, and teammate Wilkes of UCLA.

In the locker room after the 1973 Championship game, Coach Wooden introduced Walton to representatives of the ABA, who hoped to convince him to turn pro.

[54][55] In 1975–76, Walton averaged 16.1 points, 13.4 rebounds, 4.3 assists, and 1.6 blocks in 51 games as Portland, with rookies Bob Gross and Lionel Hollins, finished 37–45.

[58][54] In the 1977 postseason, Walton led #3 seed Portland to series victories over the Chicago Bulls with Artis Gilmore (2–1) and the Denver Nuggets with Dan Issel (4–2).

[59][58] In a 4–0 series sweep of the Los Angeles Lakers in the 1977 Western Conference finals, Walton averaged 19.3 points, 14.8 rebounds, 5.8 assists, and 2.3 blocks playing against fellow UCLA alum Kareem Abdul-Jabbar.

Walton scored 20 points and grabbed 23 rebounds in the clinching Game 6 victory,[63][57] and was named the Finals MVP with averages of 18.5 points, 19.0 rebounds, 5.2 assists, 1.0 steals, and 3.7 blocks,[57][63] which prompted Philadelphia 76ers coach Gene Shue to comment after the series: "Bill Walton is the best player for a big man who ever played the game of basketball.

After having received a painkilling injection to play, X-rays taken after Game 2 revealed the navicular bone below Walton's left ankle was broken.

[54] On May 13, 1979, Walton signed as a veteran free agent with the San Diego Clippers; the Portland Trail Blazers received Kevin Kunnert, Kermit Washington and a 1980 first-round draft pick (Mike Gminski was later selected) as compensation ordered by the NBA.

Walton re-fractured the navicular bone in the fourth 1979 exhibition game and subsequently missed all of the 1980–81 and 1981–82 seasons, undergoing several surgeries on his injured foot.

After several players on the Celtics said they liked the idea of having Walton as a teammate backing up Robert Parish and Kevin McHale, Red Auerbach made the deal happen.

[14] On September 6, 1985, Walton was traded by the Los Angeles Clippers to the Boston Celtics for Cedric Maxwell and a 1986 1st round draft pick (Arvydas Sabonis was later selected).

[70] In the Celtics' 4–1 series win over the Atlanta Hawks with Dominique Wilkins in the Eastern Conference semi-finals, Walton averaged 8.0 points, 3.3 rebounds, and 1.3 assists in 13 minutes.

[54] At age 17, just out of high school, in the summer of 1970, Walton was selected to represent the U.S. national basketball team at the 1970 FIBA World Championship.

In a 2004 interview with ESPN, Walton stated that "for the first time in my life, I was exposed to negative coaching and the berating of players and the foul language and the threatening of people who didn't perform.

[90] Walton overcame a stuttering problem at age 28 with the help of legendary broadcaster Marty Glickman, after a lengthy conversation between the two at an event.

But in life, being so self conscious, red hair, big nose, freckles and goofy, nerdy looking face and can't talk at all.

[136][137] Walton narrated Fire on the Mountain, an action sports documentary featuring Grateful Dead songs, which aired on ESPN in October 2020.

"[139] Dead & Company featured a memorial montage to Walton during a performance of "Fire on the Mountain" at their May 30, 2024 concert at the Sphere in Paradise, Nevada.

[142] In a June 8, 2010, interview on The Dan Patrick Show, Walton admitted to contemplating suicide for a time due to the constant pain resulting from injuries sustained during his NBA career.

[149][150][151][152] A moment of silence was held in Walton's memory before Game 1 of the subsequent NBA Finals on June 6 at TD Garden between the Celtics and the Dallas Mavericks.