William December Williams Jr. (born April 6, 1937) is an American actor, novelist and painter. He has appeared in over 100 films and television roles over six decades. He is best known for portraying Lando Calrissian in the Star Wars franchise and has also appeared in critically acclaimed and popular titles such as Mahogany (1975), Scott Joplin (1977), and Nighthawks (1981), as Harvey Dent in Batman (1989) and The Lego Batman Movie (2017), The Last Angry Man (1959), Carter's Army, The Out-of-Towners (1969), The Final Comedown and Lady Sings the Blues (both 1972), Hit! (1973), Fear City and Terror in the Aisles (both 1984), Alien Intruder (1993) and The Visit (2000).

Raised in Harlem, Williams made his Broadway theatre debut at age seven in The Firebrand of Florence (1945). He later graduated from The High School of Music & Art, then won a painting scholarship to the National Academy of Fine Arts and Design, where he won a Hallgarten Prize for painting in the mid-1950s. He returned to acting to fund his art supplies, including stage, films, and television. He continued painting; his work has since been shown in galleries and collections worldwide. Williams’ film debut was in The Last Angry Man (1959), but he came to national attention in the television movie Brian's Song (1971), which earned him an Emmy nomination for Best Actor. In the 1980s, he was cast as Lando Calrissian in The Empire Strikes Back (1980), becoming the first black actor with a major role in the Star Wars franchise. He reprised his role in subsequent Star Wars films and media. Williams's television work includes over 70 credits starting in 1966 including recurring roles over the decades in Gideon's Crossing; Dynasty, General Hospital: Night Shift; and General Hospital. Numerous cameos and supporting roles included being paired with Marla Gibbs on The Jeffersons, 227, and The Hughleys. Later work included voice acting in the series Titan Maximum (2009), and appearing on the reality show Dancing with the Stars (2014).

His work has earned him numerous awards and honors including three NAACP Image Awards, and the NAACP Lifetime Achievement award. He was inducted into the Black Filmmaker's Hall of Fame in 1984, and earned a star on the Hollywood Walk of Fame in 1985.