A game is called a BOUT. It consists of two 30-minute periods with episodes of play known as JAMS. Five skaters for each team – one JAMMER, three BLOCKERS and one PIVOT – move counterclockwise around the track in a formation called a PACK. Jams last for up to two minutes each, but can be ended sooner by the LEAD JAMMER.

The Pack

The pack is the largest group of Blockers from both teams within 10 feet of each other. Blockers in the pack act offensively to help their own Jammers score points and defensively to try and stop the opposing Jammer from scoring.  The Pivot is the lead Blocker, identified by a stripe on her helmet cover. The pack 
determines where the action is. You must be within 20 feet of the pack to block an opponent or help another member of your team.

If players get too spread out, there is no pack and they can’t block or assist other players until the pack re-forms.

If skaters do hit or assist when there is no pack, they are out of play and can be penalized.

The Jammers

Jammers wear helmet covers with stars. They line up behind the pack and start on the second whistle. Their job is to get through the pack and then lap the pack again to score points. The first Jammer to get through the pack legally earns Lead Jammer status, giving her the ability to call the jam off by placing her hands on her hips repeatedly. Starting with her second trip though the pack, the Jammer scores a point for each opposing Blocker she passes legally. She also earns points for any opponents in the penalty box after she passes her first opponent on the track. While Blockers always serve one minute for each penalty they incur, that’s not always the case with Jammers.  To keep the action moving, a Jammer will serve a shorter penalty if the opposing Jammer goes to the penalty box before a minute is up.  When this occurs, the second Jammer serves the same amount of time as the first.