Cape Town - Niki Lauda has hailed Mercedes' fourth championship double, but has warned that next year it will be "even more difficult" to achieve.
With Lewis Hamilton winning the world title to go along with Mercedes' constructors' championship, the Brackley team has, for the fourth year running, claimed the double.
It wasn't, however, an easy run.
Although the team romped to the constructors' crown, Hamilton was pushed hard by Ferrari's Sebastian Vettel in the opening half of the season and trailed by as many as 25 points at one stage.
The Brit, though, put in a stellar second half of the season to wrap up the title in Mexico with two races to spare.
Attending Mercedes' celebrations in Brackley earlier this week, Lauda warned that next season it may be even harder for the team.
"This year was the most difficult one so far and next year it will be even more difficult, but I trust the team 100 percent," said the non-executive director.
"For the fourth time in a row I'm in the fortunate position to say thank you to the entire team.
"2017 has been a challenging year because of the rule change. A rule change always means uncertainty; no one knows what the other guys are doing.
"We started with a difficult car, but the team was able to consistently improve it throughout the season, which was the key to winning the championships.
"The team did a fantastic job and Lewis did a fantastic job. I'm really proud of everyone, it's an incredible achievement."