Williams team principal James Vowles has conceded it will take "years" to make the team competitive at the top of F1's midfield.
Vowles' tenure at the Grove-based outfit got off to a promising start as Alex Albon secured a point for 10th at the Bahrain Grand Prix.
The former Mercedes strategy director took over as team principal following the departure of Jost Capito in the winter, the latest in Williams' upheaval under Dorilton Capital.
Sights are set on returning Williams to the summit of F1, with the team failing to win a race since Pastor Maldonado triumphed in Spain in 2012 and without a championship since Jacques Villeneuve in 1997, but Vowles is under no illusion that he faces a major task to achieve this goal.
Williams 'dreams' outlined
“It's incredibly difficult to get into the top three," said Vowles.
"They have resources that are beyond your dreams, they have the experience, they have the best people on the grid.
“I think a realistic step for this organization is first and foremost to make sure that each year we move forward and that we don't stay in the same place.
"This must be dream number one.
"Dream number two is to set a reasonable period in the future, and these are years, where we will start to break through for sixth, then fifth, then fourth place [in the championship]."