Nico Hulkenberg will switch to Sauber next season to replace McLaren-bound Sergio Perez.
Hulkenberg returned to drive in Formula One at the start of the year with Force India, after a season as reserve for the Silverstone-based marque.
Prior to that, Hulkenberg had spent a year with Williams, only to be dropped at the end of his debut campaign in 2010 as the team opted to recruit a pay-driver in Pastor Maldonado.
The 25-year-old German had been linked with a move after impressing at Force India this season, and with Sauber eager to fill the gap to be left void when Perez departs, they see Hulkenberg as the ideal replacement.
"We've been observing Nico for some time now, and his performances have been very persuasive," said team principal Monisha Kaltenborn.
"That was the case in GP2 and has continued into Formula One. An obvious highlight was how he scored pole at Interlagos in 2010 despite the most challenging external conditions.
"He clearly showed he can seize the chance if it arises. But high spots like that are one thing; systematic teamwork is another, and on that score I have confidence in Nico too.
"I'm sure he will fit in very well with the Sauber F1 Team. We look forward to working together with him."
With three races remaining, Hulkenberg has the edge on Force India teammate Paul di Resta, with a five-point gap between the duo as the team chase Sauber for sixth place in the constructors' championship.
Assessing his switch to the Swiss-based marque, Hulkenberg said: "It is a well-placed team and very competitive.
"Plus it's a team in which young drivers have repeatedly delivered exceptional performances. I would like to take up that baton.
"The team is currently going through a very positive development and I'm certain that together we can achieve a lot.
"Until that time I will remain fully focused on my job with Force India. I'd like to thank the management at Force India for giving me the chance to return to Formula One as a team driver."
The second seat remains up for grabs, with Sauber to make an announcement at "a later date".
Current occupant Kamui Kobayashi is known to be seeking sponsorship in a bid to hang on to his drive, but faces competition from others who can provide funds.