Michael S. Weiner (December 21, 1961 – November 21, 2013) was an American attorney who served as the executive director of the Major League Baseball Players Association for four years.

From 1986 to 1988, Michael served as law clerk to H. Lee Sarokin, then United States District Court Judge, in Newark, New Jersey.

[3] With Weiner at the helm, the union signed an agreement in November 2011 for a five-year contract running until December 2016, which ensured 21 consecutive years of labor peace in Major League Baseball.

The agreement allowed for blood testing for human growth hormone, introduced restraints on bonuses for amateur draft picks and international signings, and restored salary arbitration eligibility for part of a class of players that lost it in the 1980s.

[8] He was succeeded by his deputy, Tony Clark, the first former Major League Baseball player to lead the union.