[6][7] From 1981 to 1988, Harhart was employed as a tax collector in North Catasauqua, Pennsylvania.

A constituent liaison, office manager and legislative aide to the Republican Caucus of Pennsylvania House of Representatives from 1990 to 1994, she was subsequently elected to the Pennsylvania House for its 1995 term and reelected.

Appointed to the Joint Legislative Air and Water Pollution Control and Conservation Committee in 1995, she served in that capacity until 2008).

Appointed as Deputy Whip in 2007, she served in that leadership role until 2010.

Appointed to the Joint Conservation Committee in 2009, she served in that capacity until 2016.