Andreas Zuber is to stay on at Fisichella Motor Sport for his fourth year of GP2.
The 25-year-old Austrian had already joined Giancarlo Fisichella's squad for this winter's GP2 Asia series, and will remain with the team for the main championship.
He was a race-winner for Trident and iSport in 2006 and 2007, but had to settle for podiums with Piquet Sports last year.
Zuber is now determined to challenge for the title in 2009.
"From the first moment I stepped into the cockpit of the FMSI Dallara, I felt that it was the race car I wanted to drive in the international GP2 Series this year," he said.
"I immediately established a good relationship with my engineer and the crew and, in the end, it was an easy decision to make."
Team boss Paolo Coloni said he had been keen to sign Zuber for some time.
"We wanted Andreas to driver for us in 2008 and unfortunately he opted for another team," said Coloni. "I have learned never to give up so I invited him to test our car.
"Last season we were extremely competitive, especially in the last couple of races, and I wanted him to experience that and not just hear it from me. I am so glad he has made the decision to join FMSI because we need his speed and experience to clinch that championship victory that we have been chasing for the past three years."
Zuber has also become part of Fisichella's manager Enrico Zanarini's driver management stable.
"We have both agreed that 2009 is a make or break year for him and we will spare no time or efforts to make sure that the perfect job is done," said Zanarini.
"We have already started to reorganise his training programme and to build a commercial network behind him. He will not have to deal with any other aspect of his career that is not related to racing."