The transfer window is well underway, but here are the biggest deals (over £40m) you may have missed from around Europe so far. And check back for updates.
For a full breakdown of all transfers in Europe's major leagues, sortable by club, please click here.
Note: All fees are undisclosed and based on ESPN FC sources unless noted with *.
Well, this one came out of almost nowhere less than a month ago and one of Barcelona's star players has now moved for a new world record. It's the biggest transfer this window. This biggest transfer in history. Though Barcelona now have £198m to spend on new talent.
It's been on the cards for some time, and the money is not yet in Monaco's accounts as it won't be a permanent deal until next summer, but Mbappe has moved to PSG on loan to avoid FFP issues, before becoming the second highest transfer in the world.
Coutinho almost made the move in the summer, but eventually joined Barcelona in January 2018 for a fee that could reach £142m with add-ons. The Brazilian playmaker signed a five-and-a-half-year contract and will rejoin his old Liverpool teammate Luis Suarez.
After a few weeks of negotiations, Barcelona were able to snap up a replacement for Neymar for the mere price of €105m, rising to €147m with bonuses. Dembele, 20, is now the second-most expensive player of all time, with the winger even beating Paul Pogba's £89.3m move to Man United last season.
The most expensive defender in the world is now playing for Liverpool. Van Dijk had not been happy at Southampton and seemed set to move to Manchester City, but instead opted for a move to Anfield.
Lukaku was linked with a move back to Chelsea but chose Manchester United instead and is now a teammate of his friend Paul Pogba. Reports suggest the final price with add-ons could be a new world-record of £90m. Wayne Rooney went the other way in a separate deal.
Morata scored 15 goals in 26 appearances for Real Madrid in La Liga last season but wanted a chance to become undisputed first-choice. Antonio Conte gave him that chance.
Mendy impressed with Monaco last season and had to deal with the pressure of being the world's most expensive defender at Man City before he was injured, then overtaken by Van Dijk.
It was an interesting time at Chelsea for Diego Costa: titles, goals, fights, suspensions and, ultimately, an acrimonious exit back to the club from whence he came. Nothing is ever easy with the Spain striker and he had to wait six months to make his debut due to the club's transfer ban.
He almost moved to Atletico Madrid but due to their transfer ban, Lacazette arrived at Arsenal from Lyon this summer instead.
City have been on the lookout for full-backs and made Spurs' right-back Walker the joint-most expensive defender in history for a fee that will reach £50m with add-ons.
The Iceland international signed a five-year contract, with big-spending Everton laying out a club-record fee for a midfielder they had been chasing for some time.
Portugal international Silva won Ligue 1 with Monaco last season and caught the eye of Pep Guardiola, who snapped him up in June before any other major clubs had done business.
A reliable, selfless performer in defensive midfield, the Serbia international reunites with his former manager at Chelsea as Man United seek to win their first Premier League title since 2012-13.
Another starlet from Monaco's Ligue 1 winning side, Bakayoko chose to line up alongside N'Golo Kante in a fearsome looking midfield at Chelsea.
Arsenal lost another English player to a rival, and Liverpool got a young, hungry midfielder. The key was his contract ending in 2018 and desire to play in central midfield, something Jurgen Klopp offered over Chelsea.