In a newsletter to supporters, Hall Findlay says after a decade that included five election campaigns, two nomination battles and two leadership campaigns, it's time to focus her energy elsewhere.
She says she hopes to spend more time with family and friends, develop business opportunities and continue her work in public policy.
Hall Findlay was elected to the House of Commons in the Toronto riding of Willowdale in a March 2008 byelection.
She was re-elected in the 2008 general election, but lost her seat in 2011 to then-Conservative Belinda Stronach.
Hall Findlay ran unsuccessfully in the 2006 Liberal leadership race to succeed Paul Martin and also lost in the contest earlier this year that chose Justin Trudeau.
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