"AS Roma is pleased to announce the outright purchase of Devyne Rensch from Ajax," the club said in a statement. "Welcome to Roma, Devyne!"
Ajax will receive around €5 million for the player who came through their youth academy, while the player will reportedly earn around €1.2 million per season for the duration of his four-year contract.
He will wear the number 2 shirt and will be the eighth Dutch player in history to represent the Italian club.
"It was not an easy decision to let Devyne go at this time," said Ajax technical director Alex Kroes.
"As a homegrown player and an undisputed starter, we will certainly miss him here. He was eager to take on this new challenge, and now he has the opportunity to showcase his qualities in one of Europe's finest leagues.
"We have wished Devyne all the best and hope he will be just as successful in Italy as he has been here at Ajax."
