Coaches often need to consult with their players during a game, and this is regulated by charged conferences.
A team is allowed one conference per inning while on offense.
A defensive team conference is a little more involved because of the pitching position, which changes more often. On defense the coach (or a non-playing assistant coach) is allowed three conferences per game and, if there are extra innings, he gets one and only one conference per inning. One of the umpires is required to notify the coach of each charged conference and to make note in writing of each conference.
Note that a conference is not charged if:
a pitching change is made
a coach consults with his players during the other team’s charged conference and does not delay the game
there is an unrelated break in the action and the offensive coach consults with his players (the defensive coach is not allowed this courtesy)
A defensive conference held on fair territory ends when the coach crosses the foul line on his way back to his bench. Any other conference, defensive (held on foul territory) or offensive, ends when the coach begins to head back to his bench or position.
During the first seven innings of play, if a coach has been charged with three defensive conferences, he must replace the pitcher every time he consults with a defensive player on the field. During any extra inning, the same rule holds after one defensive conference has been charged in that inning.
[MLB allows unlimited conferences except when a second trip to the same pitcher occurs in the same inning (different batter). Conference ends when he leaves the dirt circle of the mound or an imaginary 18-foot circle around the conference location.]