[5] She decided to pursue a career in finance while on a high school class trip to the Chicago Board of Trade.
[1][6][7] In 2001, Seitz was named CEO of William Blair Investment Management (WBIM), which she grew to become the company's largest division.
[8] Serving as WBIM's CEO for 16 years, Seitz ran the institutional, mutual fund, and private wealth management businesses.
[1][9] To increase diversity at the firm, Seitz instituted a policy requiring at least half of all interview candidates must be either women or ethnic minorities.
[7] In September 2017, Seitz left William Blair in Chicago to join Seattle-based Russell Investments as CEO.
[5] Seitz is a founding member and donor to All In Seattle, a fund supporting nonprofit organizations during the COVID-19 pandemic, and a founding co-chair of the Chicago Council's Women and Global Development Forum, which encourages "inclusive global development practices" and supports women "advancing into leadership roles".
[15] She has served on the board of trustees of the Financial Accounting Foundation and chaired the organization's Finance and Compensation Committee.