Strootman joins Roma from PSV
The Holland midfielder has signed a five-year deal with the Giallorossi after the two clubs agreed a fee reported to be 20 million euros.
Strootman wrote on his personal website: "I am very excited to be able to play for this great club.
"It is the next stage in my career development after being at Sparta, FC Utrecht and PSV, a club at which I had a lot of fun."
The 23-year-old admitted he had sought the advice of PSV team-mate, and former AC Milan midfielder, Mark van Bommel before opting to move to Italy.
Strootman told De Telegraaf: "He was the man with experience of Italy.
"Mark said how great the passion of the fans was, how special the atmosphere in the stadiums was and how there was a totally different football culture.
"What counts for me is the number of big games I am going to play here.
"I will train every day with top players and get to play against the likes of Inter Milan, Juventus and Napoli."