Outgoing Renault racing president Jerome Stoll has set the target of a podium for the French works team in 2019.
Renault had targeted getting closer to the top three teams this year, and although fourth overall, team officials and drivers admitted the performance and development could have been better.
Stoll, who is retiring on December 31, said Renault underestimated how difficult it would be after buying Lotus in late 2015.
"We largely underestimated the state in which the team was in," he told France's Auto Hebdo.
"Many people had left, very little investment had been made. We knew it was going to be difficult, but we ended up in a much more difficult situation than expected," he added.
But Stoll said Renault has been making huge efforts to restructure the team for the future.
"Thanks to Cyril Abiteboul, who has been able to give the impetus, we are a team with a very special identity and it is something that makes me proud," he said.
"We were ninth in 2016, sixth last year and fourth this year, which is a first step in which we have set up all the foundations," said Stoll. "The next step for Renault is the podium."