Harrison's junior career involved reaching the semi-finals of the 1999 Ontario Juniors, winning the 1999 Ontario University championship and the provincial junior mixed championship playing third for future Olympic champion John Morris. After juniors, Harrison would win the Ontario Curling Association Tim Hortons Trophy with skip Vicky Hysop. She has also played in two mixed provincials (2008 and 2009). Harrison has played in two provincial women's championships. In 2010, her Alliston Curling Club rink finished the round robin with a 5-4 record, and won a tie-breaker match to make the playoffs. In the playoffs, she won the 3 vs. 4 game, but lost in the semi-final to Tracy Horgan. Harrison would not return to the provincials until 2013.
Harrison's first World Curling Tour event was in 2003. She has played in three Grand Slam events. Her first Grand Slam was the 2010 Players' Championships where her team went 2-3, just missing out on the playoffs by losing her final match. Her next Grand Slam was the 2010 Sobeys Slam where she finished with a 4-3 record, again missing out on the playoffs in her last match. Her third Slam of her career was the 2012 The Masters Grand Slam of Curling where she finished with a 3-2 record, losing in a qualifying match.