Ahead of the opening race of the 2017 Formula One season in Australia on March 26, we take a look at how each team is shaping up for the new campaign.
Here we assess Williams' hopes of breaking into the top three on the grid in 2017.
HOW DID THEY PERFORM IN 2016?
After two seasons finishing third in the Constructors' Championship, last year was tougher for Williams as they saw Ferrari and Force India push them down to fifth.
There were very few reliability issues for Valtteri Bottas and Felipe Massa but performance levels dropped off, with Bottas' third-place finish in Canada their only podium.
Attempts to improve their competitiveness proved unsuccessful and there have been a raft of changes within the team for 2017 - including the departure of Pat Symonds, who has been replaced by Paddy Lowe from Mercedes.
THE 2017 LINE-UP
The experienced Brazilian had been due to retire after 2016, but Bottas' move to Mercedes to replace Nico Rosberg led to his surprise return.
Massa's experience will be invaluable for the team given his team-mate is 18-year-old rookie Lance Stroll, and he has already impressed having completed 414 laps during testing, which saw him fifth fastest behind Ferrari and the Silver Arrows.
Stroll joined Williams in 2016 as a development driver and his efforts behind the scenes were enough to earn a seat for the upcoming campaign.
The Canadian has enjoyed plenty of success in his fledgling racing career, Stroll having won the Italian Formula 4 and European F3 championships since making his debut in 2014.
His initial outings in an F1 car have been problematic, though, suffering a number of crashes during testing as he tried to get to grips with the FW40.
THE TO-DO LIST
The weight of expectation cannot solely rest on the shoulders of Massa, so it is imperative for Williams that Stroll quickly gets up to speed to help the development of their car.
Tapping into Massa's vast knowledge will also be key, Williams must use his strong testing displays to give themselves a chance of challenging for more podiums this time around.
HOW WILL THEY FARE?
Testing was difficult to judge because of Stroll's struggles but as the sessions went on the youngster was able to complete important laps ahead of Australia.
Replacing Bottas' reliability may prove difficult, though, given they have two drivers at opposite ends of the spectrum.
They will have to hope Massa's pace can be replicated to keep them ahead of Force India, and maybe allow them to challenge Red Bull for third.