Ted Hsu, the first-term Liberal MP for Ontario's Kingston and the Islands riding, says he will not run for re-election in 2015 so he can spend more time with his family.
Hsu, who is married with two young daughters aged four and 11, said it was a decision he and his wife made together.
In a phone interview from his riding office on Thursday, Hsu told CBC News it was difficult to balance his responsibilities as a husband and father with his duties as an MP.
"I think that was the challenge for me, how to manage time and manage being absent from the family."
NDP Leader Tom Mulcair recently wrote to House of Commons Speaker Andrew Scheer asking him to help MPs with the work/life balance.
Hsu, whose family lives in the riding he represents, said Canadians in general would benefit from more flexible daycare services.
"I have had a lot of constituents say that they need daycare at odd hours because of shift work."
While Hsu was one of the few MPs who did not back Justin Trudeau for the leadership of the Liberal Party, he said he spoke with Trudeau just a few days ago and is leaving the party on good terms.
"He was very supportive, very understanding because of his own experience growing up as the son of a prime minister."
Hsu backed Marc Garneau and later threw his support behind B.C. MP Joyce Murray after Garneau exited the race.
Hsu was the party's natural resources critic and served on the Commons' natural resources committee in 2013, but was moved out of the position by Trudeau and appointed Ontario caucus chair and caucus accountability officer. Hsu was also named the party's critic for science and technology, post-secondary education and Ontario economic development, roles he had previously held.
Trudeau thanked Hsu for his hard work and dedication to his constituents.
“Ted has always been a strong voice and advocate for his constituents. His dedication to the people of Kingston and the Islands serves as a powerful example of how all parliamentarians ought to represent and engage with the citizens in their ridings," Trudeau said in a written statement Thursday afternoon.
"We wish him and his family well as they prepare to embark upon the next chapter of their lives.”
Industry Minister James Moore wished his Liberal counterpart well.
"All the best in the next chapter of life Ted," Moore said in a post on Twitter.
Bring back census
Hsu introduced a private member's bill last year that would strengthen the independence of Canada's chief statistician and bring back the long-form census without the penalty of a prison sentence for refusing to fill it out.
Private member's bill rarely make it into law, but Hsu hopes to re-open the conversation about the need for reliable statistics when his bill comes up for debate in the fall.
The mandatory long-form census was replaced by a voluntary national household survey in 2010 when the Conservatives scrapped it based on a few complaints from Canadians who feared being jailed for refusing to answer questions they deemed too intrusive.
Hsu quoted Prime Minister Stephen Harper, who recently said "you can't manage what you can't measure." His comments were made in the context of new funding for child and maternal health. Canada's pledge will pay for several life-saving measures including a new system to register births.
Using Harper's logic, Hsu said "let's measure this country that we're trying to govern."
Hsu said anyone interested in representing the riding should seek the Liberal nomination, even if they aren't already a public figure.
"I wasn't very well known when I ran."
Asked if his decision not to run again had anything to do with the nomination process, Hsu said it didn't.
"I got greenlit and they were going to acclaim me in a couple of weeks."
Peter Milliken, the country's longest-serving Speaker, held the seat in Kingston and the Islands since 1988 before Hsu was elected to represent the Ontario riding in 2011.