Esteban Gutierrez has been confirmed as Sauber's second driver for 2013 following the departure of Sergio Perez to McLaren.
Gutierrez, who came third in the GP2 championship this year, has completes several tests for Sauber over the last three years but he has now secured a race drive for 2013 alongside Nico Hulkenberg.
"Esteban has already been part of the team for a long time and we have followed his career very closely," team principal Monisha Kaltenborn said.
"In 2010 we signed him up as an affiliated driver, and in 2011 and 2012 he was our test and reserve driver. We mapped out his path to Formula One step by step.
"Esteban has great talent and now he's ready to take the leap. We are in no doubt we have a strong driver pairing in place for the 2013 season with Nico Hülkenberg and Esteban Gutiérrez."
Gutiérrez added: "After three years working with Sauber I feel very grateful for all the attention I have received from everyone in the team and for all their input, which has allowed me to develop into a Formula One driver in a very progressive way.
"Now, after experiencing other categories of racing as an introduction to Formula One, this is the start of the real challenge to succeed at the pinnacle of motor sport.
"The support from my family, as well as from my sponsors, has been a key factor in getting there and I am very grateful to everyone who has been involved in our project.
"It will be a great pleasure to be racing in the same team as an experienced driver like Nico Hülkenberg. He will be a good reference point for me and will push me to adapt quickly to F1 competition so we can develop the car together with the team in the best way."
Sunday's Brazilian Grand Prix will be Perez's final race for the team before he moves to McLaren and it is now known that it will also be Kamui Kobayhasi's last outing.
The Japanese competitor had hoped to remain with Sauber but confirmation of Gutierrez's signing means he could be without a drive in 2013.
Thanking him for his efforts, Kaltenborn added: "I would very much like to say a few words about Kamui Kobayashi as well. Over the last three years Kamui has shown us he is not only a fierce competitor on the track, but also a wonderful person and fantastic team player.
"Every member of our team has the greatest respect for him, and his podium in Japan was a particularly emotional moment for all of us. This has not been an easy decision for us to take, but we have committed ourselves to a new beginning and our time with Kamui will come to an end after the final two races of the season.
"We wish Kamui all the best for the future. Our thanks also go to Sergio Pérez, who has claimed three podiums for the team so far and now has the opportunity at McLaren-Mercedes to display his immense talent with one of the most successful teams in Formula One history.
"We would also like to wish Sergio all the best and every success for the future."
World Series by Renault champion Robin Frijns has been announced as the team's new reserve driver.