Girls' lacrosse is composed of four main positions: attackers, defenders, midfielders, and goalies.  Each of these positions have different roles, that when combined, make for a successful lacrosse team

Attackers:  The main job of these four players is to score goals.  Spending the majority of their time in the offensive 2/3rds of the field, these players run the offense.  With the help of the midfielders, they work to create scoring opportunities for their team.  These players typically like to set themselves up behind the goal along the crease, or at the elbow of the 8-meter arc.  However, that is not to say that attackers don't ever drive to goal from the top of the arc.  Along with scoring and running the offense, these four players also participate in the re-defend.  This means that if the offense turns over the ball, these players work to slow down the opposing defenders and try to prevent them from moving the ball down the field.

Defenders:  In contrast to the attackers, the four defenders work with the midfielders to prevent the opposing team from scoring goals.  Most elementary level defenses play a man-to-man defense, meaning each defensive player marks one opposing offensive player throughout the whole possession.  As well as playing man-to-man defense, more advanced defenses often play a zone defense as well.  This means that rather than marking individual players, the defenders rather have a zone to cover.  Therefore, any player that enters a defenders' zone is her responsibility.  Along with keeping the other team from scoring, the defense also plays a key role in transition.  If the opposing offense turns over the ball or the goalie makes a save, the defenders must work to move the ball up the field to their midfielders and attackers.

Midfielders:  Unlike the attackers and defenders who are held to just 2/3rds of the field, the three midfielders have the ability to move throughout the entire field.  This gives these players the ability to participate in the offense and defense.   This also means that the midfielders are critical players when transitioning the ball up the field or guarding the other teams' transition.  Unlike any other position, these three players also get the chance to be apart of the draw.  One of the three, the center, will takes the draw, while the other two players will be lined up around the center circle. 

Goalie:  Playing with a different type of stick and wearing different gear, the goalie position is much different from any of the field players.  The goalie is considered the last line of defense and she is the protector of the goal.  Set up inside the crease, something only she is allowed to do, the goalie uses her stick and body to keep the other teams' shots from crossing the goal line.  If the goalie does make a save, it is her role to clear the ball out to one of her teammates and initiate the transition.  After making a save, the goalie only has ten seconds in the crease, or she must exit the crease, now allowing herself to be guarded by the opposing team.  While the goalie is allowed to make her way all the way down the field if she wishes, she is not allowed to score a goal.