What has the manager said?
Speaking at his unveiling, new West Ham manager David Moyes said: "They have spent well on players. If we're being truthful, we need those players to stand up.
"They will have a massive impact on the support and they need to stand up in the coming weeks. We had to get a quick turnaround last time to get results, we have to do that again but I do know I now have a longer project.
"I think there is money there to spend. I am more interested in the players at the club at the moment, see how we can mould them into the best possible team and formation. We have to get results."
What did West Ham do in the summer?
West Ham smashed their transfer record when they bought in Sebastian Haller from Eintracht Frankfurt for £45m, with Pablo Fornals also costing £24m from Villarreal. Albian Ajeti joined for an undisclosed fee while David Martin and Roberto were free transfers.
Marko Arnautovic left the club in a £22.4m deal, signing for Shanghai SIPG, while Lucas Perez, Pedro Obiang, Edimilson Fernandes, Javier Hernandez and Reece Oxford all departed for undisclosed fees. Samir Nasri, Andy Carroll and Adrian were released.
Who have they been linked with?
Luka Jovic, Real Madrid [December 17, Fichajes]; Olivier Giroud, Chelsea [The Sun]; Joe Allen, Stoke [Daily Express]; Darren Randolph, Middlesbrough [The Sun]; Neil Etheridge, Cardiff [The Sun]; Stanislav Lobotka, Celta Vigo [Il Mattino].
Who could depart?
Issa Diop, Tottenham [December 22, Sky Sports News]; Albian Ajeti, loan [December 17, Sky Sports News]
Analysis: What to expect this January
Sky Sports News' reporter Kaveh Solhekol...
"The Hammers have two key targets during the January window and are seeking a strong, physical, box-to-box midfielder - and they have between £6m and £12m to spend.
"They are also looking to sign a goalkeeper: Lukasz Fabianski is on his way back from long-term injury and they have been reluctant to put Roberto back in the starting XI after a dreadful seven-game run in the Premier League. Again, their budget for this position is between £6m and £12m,
"As with most clubs, they are also open to signing another centre-forward, with Sebastian Haller yet to make make his real mark and fellow summer signing Albian Ajeti struggling to get in the team."
How to follow the January transfer window with Sky Sports
Sky Sports will bring you the very latest news from the January transfer market with the return of three shows.
Start your day with Good Morning Transfers at 9am as our team of reporters bring you the latest news and insight. Transfer Talk then follows at midday delivering analysis of the biggest stories. Then join us at 7pm for the definitive round-up of the day's news with The Transfer Show.
Meanwhile, the Transfer Talk podcast will also be back at the turn of the year with more expert analysis from here and across the continent.
And as well as tuning into Sky Sports News, don't miss a thing with our dedicated Transfer Centre blog.