The "30-30 Club" is a slang term used by baseball fans and sportswriters to describe the group of baseball players who have ever recorded at least 30 home runs and 30 stolen bases in the same season. There is no actual club to which these players belong. Instead the term "club" connotes the exclusivity and difficulty of entering into this group, as the skills required to hit many home runs and steal many bases are rarely found together in the same ballplayer.
The frequency of 30-30 seasons has gradually been increasing over time, such that the 30-30 club is no longer as exclusive as it used to be. Ken Williams became the founding member of the club in 1922, when he hit 39 homers and stole 37 bases, and was the sole member of the club for 34 years until Willie Mays recorded back-to-back 30-30 seasons in 1956 and 1957. Occurrences increased thereafter - there were two more 30-30 seasons in the 1960s, five in the 1970s, seven in the 1980s, and 20 in the 1990s.
However, with the stolen base increasingly falling out of favor as an offensive weapon, it seems likely that the 1990s will be the high water mark of for 30-30 club seasons. Although there were 17 30-30 seasons recorded in the 2000s, representing the second highest total after the 1990s, the pace is slowing noticeably, and is likely to continue to decline in the future.
The father and son duo of Bobby Bonds and Barry Bonds share the record for the most 30-30 seasons with five apiece. Alfonso Soriano still has a shot to tie or break that record as he already has recorded four 30-30 seasons. Otherwise, Howard Johnson had three 30-30 seasons, but no other player has had more than two.
At present there are 38 members of the 30-30 club and 13 have achieved the feat more than once. Four of them are members of the even more elite 40-40 club - founding member Jose Canseco, Barry Bonds, Alex Rodriguez, and Alfonso Soriano. No one has ever reached 50-50 in a season so far.
As of 2017, the members of the 30-30 club are (in order of induction, with years in which they achieved 30-30, 40-40 years in bold):
- Ken Williams - 1922
- Willie Mays - 1956, 1957
- Hank Aaron - 1963
- Bobby Bonds - 1969, 1973, 1975, 1977, 1978
- Tommy Harper - 1970
- Dale Murphy - 1983
- Joe Carter - 1987
- Eric Davis - 1987
- Howard Johnson - 1987, 1989, 1991
- Darryl Strawberry - 1987
- Jose Canseco - 1988
- Barry Bonds – 1990, 1992, 1995, 1996, 1997
- Ron Gant - 1991, 1992
- Sammy Sosa - 1993, 1995
- Dante Bichette - 1996
- Ellis Burks - 1996
- Barry Larkin - 1996
- Jeff Bagwell - 1997, 1999
- Raul Mondesi - 1997, 1999
- Larry Walker - 1997
- Shawn Green - 1998
- Alex Rodriguez - 1998
- Preston Wilson - 2000
- Bobby Abreu - 2001, 2004
- Jose Cruz, Jr. - 2001
- Vladimir Guerrero - 2001, 2002
- Alfonso Soriano - 2002, 2003, 2005, 2006
- Carlos Beltran - 2004
- Brandon Phillips - 2007
- Jimmy Rollins - 2007
- David Wright - 2007
- Hanley Ramírez - 2008
- Grady Sizemore - 2008
- Ian Kinsler - 2009, 2011
- Ryan Braun - 2011, 2012
- Jacoby Ellsbury - 2011
- Matt Kemp - 2011
- Mike Trout - 2012