The League Championship Series (LCS) is the semifinal round of postseason play in Major League Baseball which has been conducted since 1969. In 1981, and since 1995, the two annual series have matched up the winners of the Division Series, and the winners advance to meet in the World Series. The LCS comprises the American League Championship Series (ALCS) and National League Championship Series (NLCS). History The League Championship Series was created in , when both the National League and the American League increased in size from ten teams to twelve with the addition, via expansion, of the Montreal Expos and San Diego Padres to the former and the Kansas City Royals and Seattle Pilots (now the Milwaukee Brewers of the NL) to the latter. Both leagues then formed Eastern and Western Divisions, the first-place teams from which faced off in the LCS. For its first sixteen seasons, the League Championship Series were best-of-five, using the format in which the team without home field advantage hosted the first two games, and the team with it hosted the rest of the LCS, making it impossible for the disadvantaged team to win the series at home. It also allowed those teams the unusual luxury of starting a series at home, possibly having home-field advantage in a three-game series, and a guarantee that they play two games at home. In , the LCS was lengthened to best-of-seven games in the format with the team holding home-field advantage opening the series at home and playing the next three games on the road, before returning home for two more possible games. The disadvantaged team would have had more games played at home than on the road if the series ends in five games. Since , the LCS has matched up the winners of the Division Series, which were added when both leagues realigned into three divisions. Until , the home-field advantage in the LCS was allocated on a rotating basis between the two (three from 1995 through ) division champions; since 1998, that advantage is given to the team with the better regular season record, except that if a division champion faces a wild card team, the division champion always gets home-field advantage regardless of record. As of , all thirty MLB teams have reached the LCS at least once. The Houston Astros and Milwaukee Brewers are the only teams to have played in both