Henri-Paul Rousseau, president and CEO of the Caisse de dépôt et placement du Québec has announced his resignation, the Caisse said Friday.

Rousseau has been with the Caisse since September 1, 2002 and according to the announcement, he will remain as an advisor to the Caisse’s Board of Directors and officers for a three-month period ending August 31, 2008.

Rousseau is leaving to become vice-chairman of the board at both Power Corp. of Canada and Power Financial Corp. on January 1, 2009. In a release shortly following his departure announcement from the Caisse, the companies reported that Rousseau will be nominated for election to the boards of both corporations at the upcoming annual meeting.

The Caisse’s chief investment officer Richard Guay is set to assume Rousseau’s responsibilities on an interim basis until a new president and CEO has been appointed. Guay joined the Caisse in 1995 and has been chief investment officer since 2006.

“The publication of the 2007 results coincided with the end of a first full five-year mandate at the helm of the Caisse, a significant milestone on which I had to reflect. Since the Caisse’s new incorporating act, adopted in 2004, sets the president and chief executive officer’s mandate at five years, the time was also conducive to a change in management, particularly since the next six months will be devoted to drafting the organization’s 2009-2011 strategic plan. As for me, at age 60, this is the right time to take up a new challenge in the private sector,” said Rousseau, in a release.

“The Board is very sorry to see Mr. Rousseau go. He has made his mark as a great leader of this institution,” said board chairman Pierre Brunet. Brunet pointed out that the Caisse achieved excellent financial results under Henri-Paul Rousseau, ranking, over five years, in the first five percentile of Canada’s major pension fund managers.

According to the Caisse, between 2002 and 2007, depositors’ net assets doubled from $77.7 billion to $155.4 billion.

Rousseau will receive a severance pay equal to one year’s base salary and he is also eligible for pension benefits, said the Caisse.

Meanwhile, Rousseau indicated that his personal assets will continue to be managed, as they have been since 2002, by a blind trust until December 31, 2008.

The board of directors is responsible for appointing the president and chief executive officer, subject to the government’s approval and a seven-member committee chaired by Brunet will handle this.