Priority

Priority (Japanese: 先制 preemption) is a characteristic of moves, such that any move with a higher priority than another will always be performed first. When two moves have the same priority, the users' statistics will determine which one is performed first in a.

Mechanics
Each move has a hidden priority value in the game data, with values ranging from +5 to -7. The great majority of moves have no special priority: their priority value is 0. A move with a positive priority is a priority move (Japanese: 先制攻撃 preemptive attack). Moves with a positive priority may also be referred to as having an increased priority and moves with a negative priority a decreased priority. In the fandom, moves that have the same priority are said to be in the same priority bracket.

Pokémon with the Ability or  increase the priority of their  moves (only if the user has full HP in Generation VII) or status moves by 1 (respectively). Pokémon with increase the priority of most HP-restoring moves by 3.

Moves with increased priority can be blocked if a Pokémon is protected by, if it or one of its allies has the Ability or , or if it is on the ground while  is in effect. In Generation V, however, Quick Guard does not block moves that gain an increased priority from Prankster. Since Generation VII, Pokémon are also protected from moves from foes if they gained priority from Prankster.

Move priority is not affected by the effects of, which only reverses the Speed-resolved order of moves within a priority bracket; moves with higher priority are still performed before ones with lower priority. Some held items and also affect a move's resolution within its priority bracket (ignoring even Trick Room), but not the priority itself. The items Full Incense and Lagging Tail and the Ability cause the affected Pokémon to go last in its priority bracket, while the items Quick Claw and Custap Berry cause the user to go first in its priority bracket.

Certain actions always occur before any moves can be performed (with the possible exception of Pursuit). The messages for the activation of, Custap Berry, and O-Powers are always shown before anything else. Switching out, rotating, using items, escaping, and the charging messages of, and  are displayed or performed next. Mega Evolution generally occurs after any switching has occurred. If a Pokémon is Mega Evolving or rotating and using Pursuit on a Pokémon that is switching out, however, the Mega Evolution or rotation always happens before the Pokémon uses Pursuit (and therefore before the other Pokémon's switch).

is a special exception to the general rule of priority, due to its effect. Switching fundamentally happens before any moves can be performed, but when Pursuit is targeting a Pokémon that switches out, it will hit the Pokémon before it can switch, meaning that it will go before any other move, no matter its priority. If multiple Pursuits are targeting the same Pokémon and the Pokémon switches out, if the Pokémon faints before all of the Pursuits have executed, the remaining Pursuits will execute at their normal priority.

In the anime
In the, priority is rarely mentioned though priority moves such as are frequently used.

touched on the subject in A Grand Fight for Winning! while watching the Contest Battle between and Zoey in the final round of the Sinnoh Grand Festival, during which Zoey's Glameow used  and caused Dawn's Piplup to, making him unable to use.

Trivia

 * Since has a higher priority than, , , , and , they are unable to break the focus of a Pokémon using Focus Punch. They and Focus Punch are therefore the only six attacks that can strike a Pokémon in the same turn as it successfully uses Focus Punch, without the use of  or.
 * can learn more moves with non-zero priority than any other Pokémon, with 14 and 2 decreased priority moves.
 * Since charging Focus Punch had a higher priority than switching in Generation III, in a Double Battle, if the player selected Focus Punch then cancelled the selection, then switched that Pokémon out, it would still begin charging Focus Punch before switching. Its high priority also gave it the odd effect of occurring before the opponent used their items or Pokémon were switched out.
 * All moves that have ever had -7 priority have the word "room" in their names.
 * In the Pokémon Mystery Dungeon series, due to the inability to apply the concept of priority because the Speed stat did not exist prior to Super Mystery Dungeon and does not determine the attacking order, moves that are priority moves in the core series games become moves that have a range of 2 tiles.

In other languages
Priority move