It's that time when clubs scramble to strengthen their squads, to find a player who can shoot them to glory or one who can save them from relegation.
Some are flops soon to be forgotten, while others go on to become club legends.
But who has been the best January signing? We are not just talking goals, but their value and contribution to the club.
Take a look at our shortlist below and decide for yourself.
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The African champions take on the Europeans in Jeju, South Korea, as they look to seal a place in the quarter-finals.
Chambeshi has watched his side play some attractive football in the group stage and is looking for more of the same on Wednesday.
"They have a strong team but we are the African champions, so at least that morale is motivating us a lot," said Chambeshi.
He said his team had fully recovered from the 1-0 defeat they suffered against Costa Rica in their final Group C match.
"We are representing Africa and I think we have the strength and power to match Germany.
They have a strong team but we are the African champions
"We have to respect them, but they have to respect us too."
Zambia's prospects have been boosted by the return of captain Solomon Sakala who sat out the Costa Rica game through suspension.
"I'm happy the captain is back in the team; morale is high and the boys are looking forward to the game."
Chambeshi was part of Zambia's Olympic squad thrashed 4-0 by Germany during the 1988 Games in Seoul.
However, he said revenge was not his main motivation but getting the result to see them through to the next stage.
"In football, there is no revenge; we know everyone is looking at that [Seoul '88 defeat], but we buried that Seoul Olympics defeat.
"We have to do our very best so that we overcome Germany.
"That time Germany had [Jurgen] Klinsmann who was a high-class player.
"We also had good players, but now it's a different scenario."

Draped Seated Woman was moved from a council estate in Stepney, east London, on loan to Yorkshire Sculpture Park in 1997.
In 2012 Tower Hamlets Council decided against selling the piece after strong criticism.
The council said it would be positioned in Canary Wharf from October.
The Henry Moore Foundation's director Godfrey Worsdale said the foundation was "very pleased" the piece was "returning to Tower Hamlets after a careful and rigorous process".
Yorkshire Sculpture Park said it was "working closely with Tower Hamlets, following [current] Mayor John Biggs' manifesto pledge to return the sculpture to London".
Mr Biggs' predecessor, Lutfur Rahman, was removed from office after he was found guilty of electoral fraud in his 2014 election.
In 2012 Mr Rahman said it was necessary to sell the Moore sculpture - known as Old Flo - which was believed to be worth about Â£20m, because of "unprecedented" budget cuts.
Moore, a well-known socialist, sold the cast at cost price, Â£7,400, to the former London County Council on the understanding it would be displayed in a public space and might enrich the lives of those living in a socially deprived area.
The Tate Gallery described it as "part of a post-war revival of civil aspirations and social reform".
An open letter, written in 2012 by the sculptor's daughter Mary Moore and others, including film director Danny Boyle and the Tate's Sir Nicholas Serota, said selling the piece was "against the spirit of Henry Moore's original sale to London County Council at a favourable price on the understanding that it would be placed in east London".
1961 Stifford Estate, accommodating about 1,700 people, is completed
1962 Draped Seated Woman is purchased by London County Council and later placed on the estate
1997 The sculpture is loaned to Yorkshire Sculpture Park
1999 Stifford Estate is demolished
2012 Lutfur Rahman announces he wants to sell the sculpture, worth about Â£20m
2015 The High Court confirms Tower Hamlets Council is the legal owner of the sculpture after a dispute with Bromley Council which began in 2012
2017 Sculpture's return to London announced.
The January transfer window is about to close for another year.
[NEXT_CONCEPT]
Zambia coach Beston Chambeshi says his team is highly motivated for Wednesday's Fifa Under-20 World Cup tie against Germany.
[NEXT_CONCEPT]
A Henry Moore sculpture which was the focus of a dispute when Tower Hamlets' former mayor wanted to sell it is to return to the capital after 20 years.