Parkinson's father, Hank, worked in advertising, public relations and political consulting.

In 1996, Parkinson left his law practice to develop elder care facilities in Kansas and Missouri.

[4][7][6] In May 2006, Governor Kathleen Sebelius announced that Parkinson had switched parties and was her running mate for her reelection campaign, succeeding retiring Lieutenant Governor John E. Moore, also a former Republican who had switched parties shortly before he joined a ticket with Sebelius.

Parkinson's business experience and track record of working with both Republicans and Democrats were the reasons Sebelius stated for choosing him.

As chairman of the American Recovery and Reinvestment Act Advisory Group, Parkinson helped decide how to spend federal stimulus funds allocated to Kansas.

[9][10][11] In March 2009, President Barack Obama announced Sebelius as his nominee for United States Secretary of Health and Human Services.

[12][13][14][1][6] During his time as governor, Parkinson had to implement spending cuts and tax increases in order to manage a budget deficit.

Under his leadership, the state developed a comprehensive energy policy including net metering, and a 10-year plan for maintaining transportation infrastructure.

Parkinson signed legislation to create a private cause of action for victims of child pornography.

[15][16][7] Citing his bipartisan support and ability to move the state forward in challenging economic times, The Topeka Capital-Journal named Parkinson "Kansan of the Year" in 2009.

[18][19][20][21] As of 2020, Parkinson is president and chief executive officer of the American Health Care Association (AHCA) and National Center for Assisted Living.

Parkinson helped heal a major rift in the AHCA/NCAL and brought numerous providers who left to form their own association back into the fold.