It's that time of year again. The football world is about to go transfer crazy as clubs bid to rush through the last-minute deals that could make all the difference between a battle for survival, mid-table mediocrity or even a championship tilt.
Here Sportsmail's Laura Williamson brings you the lowdown on transfer deadline day. And remember, the clock is ticking.
When does it all end?
At 6pm today. That's it until midnight on December 31, when the fun starts all over again
Can players still move abroad when the transfer deadline has passed in England?
Yes, as long as the transfer window is open in the country they want to play in. From January 15 to April 15, for example, a player based in England would be allowed to move to the USA as Major League Soccer's pre-season window is open. Such a loophole also allowed Robbie Keane to move on loan from Tottenham Hotspur to Celtic last January.
The English transfer window closed at 5pm on January 31 but transfers could be conducted in Scotland until midnight.
Why is that?
FIFA stipulates national football associations can have two 'transfer windows'. The first starts at the end of the season and cannot exceed 12 weeks. The second occurs during the season and should be no longer than four weeks. But the specific dates are set by individual countries.
In Sweden, for example, the pre-season window is January 1 to March 31 and the mid-season equivalent falls between July 1 and July 31.
Home-grown: Arsenal midfielder and captain Fabregas qualifies despite being born in Spain
Are there any other exceptions?
Free agents can be signed by a club at any time during the season.
What about loan deals?
In the Barclays Premier League, players cannot be loaned out in the same transfer window in which they were bought and cannot play against the club who own their registration.
Clubs can take no more than four players on loan in one season. They can only have two on loan from other English clubs at any time and can loan no more than one player from a particular club.
But it's different in the Football League, isn't it?
Yes. The loan window opens a week after the transfer window has closed and shuts again at 5pm on the fourth Thursday in November. It will re-open from the first week of February until 5pm on the fourth Thursday in March.
Can Football League clubs bring in as many loan players as they like?
No. Clubs can have a maximum of four players under 23 and a further four players over 23 on loan during any one season. They can only name five loan players on the team sheet of 16 for a particular match and can take up to four players from one club.
Oh, and as we have seen with Craig Bellamy's move to Cardiff, the Football League club does not necessarily have to pay all of the loan player's wages.
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So what are emergency loans?
The Premier League board can authorise the loan of a goalkeeper in circumstances it considers to be 'exceptional'. This is generally when two of a club's three senior goalkeepers are injured.
This happened last season when Manchester City signed Sunderland's Marton Fulop late in April. Shay Given was injured and his understudy, Joe Hart, was on loan at Birmingham City.
When do the Premier League clubs' squads have to be announced?
By 5pm tomorrow. Clubs can register squads of up to 25 players, eight of which must be 'home-grown'.
Home-grown does not necessarily mean English, though. Arsenal's Cesc Fabregas falls into the category because he was affiliated to an English or Welsh club for three seasons or 36 months prior to his 21st birthday.
Clubs can also supplement their squads with unlimited players who are under the age of 21 on January 1 2010.
Can clubs change their squads once they've been submitted to the Premier League?
Yes - but only when the transfer window re-opens at midnight on December 31. Moves would, however, be allowed in 'exceptional circumstances'.
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