Football lawmakers are expected to approve the use of concussion substitutes from next month. Sky Sports News' chief reporter Bryan Swanson looks at the key issues ahead of the IFAB Annual Business Meeting on Wednesday morning.
What will football chiefs talk about?
There are four main items on the agenda: Concussion substitutes, five substitutes, offside and Video Assistant Referees (VARs).
IFAB will consider whether to extend the use of five substitutes beyond August 2021.
It is down to each competition to decide whether to use additional substitutes and, at the moment, the Premier League has chosen to use only three substitutes this season, after two votes of its 20 clubs.
But there is nothing in football law to prevent them from changing their mind, and there is a Premier League club meeting scheduled on Thursday.
Elsewhere, there is an ongoing review of offside, to ensure the spirit of attacking play, and, since July, FIFA has assumed all operational responsibility of VAR.
Is concussion substitutes the biggest issue?
Yes, it is a fundamental change to the game.
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It is an emotive issue and a green light for trials will inevitably turn attention onto every competition in world football.
Which competition wants to run the risk of not adopting trials and potentially risking player safety in the process? At best, it could leave them exposed to criticism from all quarters.
In October, IFAB's Concussion Expert Group said it: "… emphasised that the protection of players is the main goal and that a clear and uniform approach is needed, which can operate effectively at all levels of the game".
The group agreed that "… applying an 'if in doubt, take them out' philosophy would be the best solution to safeguard the health of football players".
When can trials take place?
IFAB is expected to formally approve trials from January.
The rule will allow teams to replace a player with a head injury even if they have made all their substitutions.
To avoid misuse, the opposing team will also be allowed to make a change at the same time.
The Football Association wants to implement the trials at the earliest possible stages of the Men and Women's FA Cup.
Following an FA Women's Super League and FA Women's Championship Board meeting on Monday, the FA confirmed that both leagues would also support the trials of an additional permanent substitution for concussions.
Will anything else be discussed?
Any Other Business is the final item on the agenda, and it is the chance for officials to raise any other issues in the game, which could include anything from handball to further clarification in relation to coronavirus protocols.
Nothing is off the table.
Who makes these decisions?
IFAB is comprised of the four British associations and FIFA.
This year's business meeting will be chaired by Jonathan Ford, the Football Association of Wales' chief executive.
Prominent officials on the conference call will include David Ellerary, IFAB technical director, Pierluigi Collina, FIFA chairman of referees' committee and Arsene Wenger, FIFA's chief of global football development.