A bout (an encounter between two fencers) in any discipline, is fenced on a field of play called a piste, measuring 2m X 14m, which is constructed of conducting material and electrically linked to the registering apparatus.
The bout is controlled and judged by a referee.
  Hits made in various forms, are indicated via coloured lights on an electric registering and scoring apparatus. Hits are registered via electric circuitry in the fencerís weapons and clothing, connected to the apparatus via cabling on spring-loaded reels. The referee awards hits, based on the indications of the registering apparatus, and on his or her analyses of the phrasing of the actions of the combatants.
Each discipline (weapon) has its own particular rules regarding valid or invalid hits and phrasing.

By fencing phrasing is meant the sequence of actions executed by the combatants i.e. attack, defence, counter-attack, renewal, stop-hit, etc., which each have certain priorities, and which culminate in a scoring or non scoring hit.

Before commencement of a bout, the referee will check that the fencerís equipment bears the mark of the weapon check authority, and may do further on-piste control checks.