From 1991 to 1995, Lensink served as a member of the Young Liberal Executive, and in July 1995 she was elected South Australian Young Liberal President where she served for two years. In January 1996, she became the Federal Young Liberal Movement's Treasurer. In 2001, she was selected at number four on the Liberal Party's
Senate ticket for the
2001 federal election; however, did not achieve the necessary quota. Appointed to the Legislative Council in May 2003 following a casual vacancy caused by the resignation of
Diana Laidlaw, Lensink was elected for a further eight-year term at the
2006 election and has subsequently held a number of shadow ministerial positions including shadow responsibility for mental health and substance abuse, security and infrastructure, gambling, government enterprises, consumer affairs, environment and conservation, sustainability and
climate change, the status for women, and for youth. She was re-elected for another eight-year term at the
2014 election. ==References==