During a Jam, each team fields up to five Skaters. Four of these Skaters are called “Blockers” (together, the Blockers are called the “Pack”), and one is called a “Jammer.” The Jammer wears a helmet cover with a star on it.

Players skate on four-wheeled ("quad") roller skates, and are required to wear protective equipment, including a helmet, wrist guards, elbow pads, knee pads, and mouth guards. All current sets of roller derby rules explicitly forbid inline skates for players.

Derby is prevalent in the United States with women's men's, co-ed, and junior leagues utilizing one another to further expand the sport.