Wiessmann is a public finance professional and has helped fund infrastructure, schools, and hospitals throughout her career. Prior to her term as Treasurer of Pennsylvania, served as a deputy director of finance for the city of Philadelphia, where she helped manage the city's debt offerings. She also served as a vice president of public finance at Goldman Sachs.
From 1990 through 1999, Wiessmann was a founding principal and president of Artemis Capital Group. The firm specialized in public finance and was ranked within the top ten municipal underwriters by the end of the decade. Later, she served as a director of public finance for Merrill Lynch, the International City Managers Retirement Corporation (ICMA), and Vantagepoint Funds.[2]
Women Creating Change awarded Wiessmann the Civic Spirit Award in 1996. The National Women Executives in State Government Association awarded her the "Breaking the Glass Ceiling Award" in 1999. In January 2014 the organization Women in Public Finance honored Ms. Wiessmann for her service to the financial industry, and helping represent women in the industry.
On February 10, 2020, Wiessmann was named executive director and CEO of the Pennsylvania Housing Finance Agency.[6] In April 2022, Wiessmann was nominated by President Joe Biden to serve as a member of the board of directors of Amtrak.[7] Her nominated was resubmitted in January 2023 but expired a year later.[8]