The versatile Italian became Paolo Di Canio's latest signing of the summer after completing his move from Serie A champion Juventus.
The midfielder, who penned a four-year deal at the Stadium of Light, is eager to become a success in England and thanked former coach Antonio Conte for guidance during his career.
"I am full of enthusiasm and want to do good things as part of this adventure," Giaccherini told Sky Sport Italia. "I want to thank [Juventus] coach Antonio Conte. In the last two years he has given me the possibility to shine and make a name for myself here.
"A big part of my success is down to him. I thank him for that and will do so personally in the next few days.
Giaccherini notes that his move comes ahead of the season leading into the 2014 FIFA World Cup, and he is keen to prove his worth both domestically and internationally to cement a place at the Brazil-based tournament.
"I have got into the national team now and I want to stay there. I will do everything for that," Giaccherini said. "I hope this new adventure can push me to the World Cup. I will do my best playing in the English championship, which is the best in the world.
"Yesterday I spoke with Paolo Di Canio. For me, due to the fact that I don't know the language, he will be a fundamental reference point - especially on the field."
Giaccherini made just 17 league appearances for Juventus last season but impressed for Italy at the Confederations Cup. He joins American striker Jozy Altidore as part of Di Canio's summer imports charged with improving a side that avoided relegation by just three points.