William J. "Kid" Gleason (October 26, 1866 – January 2, 1933) was an American professional athlete and Major League Baseball player and manager. Gleason managed the Chicago White Sox from 1919 through 1923. His first season as a major league manager was notable for his team's appearance in the World Series and the ensuing Black Sox Scandal, but Gleason was not involved in the scandal. After leaving the White Sox, Gleason was on the coaching staff for the Philadelphia Athletics until 1931.

Gleason was born in Camden, New Jersey. He acquired the nickname "Kid" early in life, not only because of his short stature (growing to only 5-foot-7, 155 pounds)[1] but also because of his energetic, youthful nature.Gleason played two seasons in the minor leagues of northern Pennsylvania. In 1886 at Williamsport of the Pennsylvania State League, he batted .355 and stole 20 bases in 36 games.[2] Gleason debuted as a pitcher with the Philadelphia Phillies on April 20, 1888. He enjoyed several successful seasons, especially 1890 (38 wins), before becoming a second baseman. He was the starting second baseman for the old Baltimore Orioles in 1895. Gleason compiled a .261 career batting average before retiring after the 1912 season. With his two at-bats in one game in 1912, he became a member of the small group of men, 29 to date, who have played major league baseball in four decades.

Gleason returned to the major leagues in 1912 as a coach, before becoming manager of the Chicago White Sox on December 31, 1918. In his first season, the team won the pennant but lost the World Series to the Cincinnati Reds, resulting in allegations that the White Sox had been paid by gamblers to "throw" the Series. The ensuing scandal resulted in lifetime bans from baseball for eight White Sox players. Gleason, however, was not involved in the gambling, and some sources note that he was among those who alerted White Sox ownerCharles Comiskey of the fix. Although he felt betrayed and disappointed by his 1919 team, he continued to manage the White Sox until 1923.

After leaving in 1923, Kid Gleason would go on to coach under manager Connie Mack with the Philadelphia Athletics until retiring after the 1931 season.[3] Gleason would win two World Series championships with the Athletics, in 1929 and 1930. Kid Gleason died of a heart ailment in 1933, at the age of 66, in Philadelphia, Pennsylvania, his funeral was well attended, a testament to his popularity. He is buried in Philadelphia's Northwood Cemetery.

Gleason has been referenced in pop culture in several books, and is a prominent supporting character in Ring Lardner's 1916 novel You Know Me Al. He is portrayed by actor John Mahoney in the 1988 film Eight Men Out, based on Eliot Asinof's book of the same name

Kid Gleason at home plate before the start of the 1919 World Series