Dallaire tells a news conference in Ottawa that will leave the Senate on June 17 in order to focus more attention on his growing portfolio of international humanitarian work.
He says his decision has nothing to do with the shadow of scandal that has loomed over the Senate for more than a year, or with the post-traumatic stress disorder that resulted from his Rwanda experience.
Dallaire, a former lieutenant-general who retired from the Canadian Forces in 2000, was appointed to the Senate in 2005 by Paul Martin, then prime minister.
He made headlines in December when he fell asleep at the wheel of his car and crashed into a traffic barrier on Parliament Hill — an accident he attributed to the stress of the upcoming Rwandan anniversary.
Indeed, Rwanda left a permanent mark on Dallaire, who still bears the mental and emotional scars of bearing witness to the bloody genocide that erupted there in the spring of 1994.
As the world marked the tragedy's 20th anniversary last month, Dallaire complained bitterly about lessons he says have gone unheeded — including his sense that the Conservative government wants little to do with the UN.
Dallaire has long used his role as senator to champion the needs of military veterans.
He also recently pressed the Conservatives to build a replica of the Vimy Ridge monument known as Mother Canada in Gatineau, Que., across the Ottawa River from Parliament Hill.