Manchester City have signed Bournemouth centre-back Nathan Ake for £40m.
The Netherlands international, who has agreed a five-year contract at Etihad Stadium, described joining Pep Guardiola's side as a "dream".
"Pep is a manager admired across the world. What he's done in the game speaks for itself," said 25-year-old Ake.
"The success he's had is unbelievable and the style of football he plays really appeals to me."
It is understood there is an additional £1m in add-ons as part of the deal.
Ake becomes City's second summer signing following the £21m arrival of Valencia winger Ferran Torres, 20, on Tuesday.
Ake joined Bournemouth in 2017 for a club record fee and made 121 appearances.
'Ake fits Guardiola template superbly' - analysis
BBC Sport's Simon Stone
One of the obvious reasons why City lost the Premier League title to Liverpool was their failure to sign a replacement for Vincent Kompany.
It is significant that after the 3-2 defeat by Norwich on 14 September, Guardiola's two most experienced central defenders, Nicolas Otamendi and John Stones, did not start another Premier League game together until July.
Both stayed on the bench throughout the rematch with Norwich, when 19-year-old Eric Garcia started, before being replaced by Fernandinho at half-time.
It is a prerequisite for Guardiola that his defenders are able to take passes in tight situations and trigger attacks. Ake fits this template superbly.
He is also good in the air, which is one of 35-year-old Fernandinho's weaknesses after he was pressed into service in the makeshift role as Stones or Otamendi - and sometimes both - were ignored.
It might not be the end of the spending either, with more defensive reinforcements anticipated.
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