Vaillieres was however defeated by the Parti Québécois in 1976 when they gain power for the first time ever under the leadership of René Lévesque.

When Daniel Johnson, Jr. replaced Bourassa during the final months of the Liberal Mandate, Vallieres was named once again the chief Whip of the government.

When the Liberals regained power in 2003, Vallières, who won a seventh mandate was named for the third time the Chief Government Whip.

However, during his mandate, health issues forced him to take some time off and Laurent Lessard took over temporarily his duties.

Vallières won an eighth mandate but was removed from the Cabinet and named the Chair of the government Caucus.