The Pirates acquired right-handed pitchers Miguel Yajure and Roansy Contreras, infielder Maikol Escotto and outfielder Canaan Smith from the Yankees in the deal.
The 29-year-old Taillon was the No. 2 overall pick in the 2010 MLB Draft and was a 14-game winner for Pittsburgh in the 2018 season. But the right-hander appeared in only seven games in 2019 and missed all of last season while recovering from Tommy John surgery on his throwing elbow.
Taillon, who has spent his entire major league career with the Pirates organization, said on social media that it was a "bittersweet day" for him.
"Bittersweet day for me over here! Trying to process everything -- have so much to say to the city of Pittsburgh and my teammates," Taillon wrote Sunday on Twitter. "Also have so much to say about this incredible opportunity and to the city/fans in New York. Thanks to everyone that has reached out! More to come soon."
The Yankees agreed to the Taillon trade less than two weeks after signing former American League Cy Young Award winner Corey Kluber, who also is attempting to rebound from injury-plagued seasons. If healthy, Taillon and Kluber could provide the Yankees with much-needed depth in their rotation behind ace Gerrit Cole.
Taillon posted a 2-3 record and 4.10 ERA in seven starts during the 2019 season. He went 14-10 with a 3.20 ERA in the 2018 campaign.