The Portuguese playmaker will arrive at the Etihad having just helped the French side to the Ligue 1 title and the Champions League semi-finals.
He began his career at Benfica, where he impressed for their B side in the Segunda Division, and in the summer of 2013 he went to the Under 19 European Championships where he was named in the top 10 talents by UEFA reporters after helping Portugal to the semi-finals of the competition.
He moved to Monaco in 2014 on a season-long loan move having made three appearances for Benfica's first team – but so impressive were his displays in France, the deal was made permanent six months into the agreement.
Silva’s guile helped them finish third in Ligue 1 and reach the quarter-finals of the Champions League, where they beat Arsenal in the last 16 after a brilliant first-leg victory at the Emirates put them in a commanding position.
Having finished third in Ligue 1 again the following season, Leonardo Jardim’s attacking revolution began to gather pace in 2016/17.
Alongside the likes of Radamel Falcao, Fabinho, Benjamin Mendy, Thomas Lemar and Kylian Mbappe, Silva was instrumental in Monaco winning the French title and reaching the Champions League semi-finals, where they beat Tottenham twice in the group stage before eliminating City and Borussia Dortmund in the knock-out phase en route to the last four.
Silva made 51 appearances last season, scoring 10 goals and assisting a further 10, making him one of Europe’s most sought-after playmakers.
He made his senior international debut for Portugal in 2015 in a game against Cape Verde and already has 12 caps.
The agreement between City and Silva comes amid interest in the player from a host of top Clubs across Europe.
The 22-year-old, who intends to take the number 20 shirt next season, said:
“It feels great. To be honest I’m now at one of the best teams in the world. To be part of this club and to have this opportunity is great.
"I’m very happy to be part of Manchester City’s team and I look forward to trying to do my best to help the team reach their goals.
"Of course when you have the opportunity of being trained by Pep Guardiola, you don’t say no.
"As we all know, what he did in Barcelona and Bayern Munich was amazing and we expect also here that he will win titles. It’s great to be working with him and to have this opportunity.”