The two Coach's box are situated in foul territory down the first and third base lines. The first-base coach and the third-base coach are supposed to stay within the confines of their respective box, measuring 15 by 35 feet, and set up 75 feet away from home plate.
The box was first added in the American Association in 1886 as a result of lobbying from Baltimore Orioles manager Bill Barnie, as a response to unsportsmanlike practices by third-base coaches of the day, who would find various ways of interfering in the play by roaming away from their position; Arlie Latham of the St. Louis Browns was a particularly active offender. The proposal was adopted immediately and has since become a standard feature of the field.
In the major leagues, there is a designated first-base and third-base coach on every team, and these two persons will stand in their respective boxes when their team is at bat. In exceptional circumstances, another coach or a manger may stand in the place of a coach. In the All-Star Game however, the coaches tend to rotate, and even the honorary team captain will - health allowing - also occupy the the coach's box at some point. In the minor leagues, there are often not enough coaches to man both boxes, so the manager or a player will take one of the coaching position, which was in fact the case in the early years of major league baseball.
Following the tragic death of Mike Coolbaugh after being hit by a foul ball while performing first-base coaching duties in a minor league game in 2007, coaches have been mandated to wear batting helmets while on the field, starting in 2008.