Clarke graduated from the University of Toronto in 1969 with a Bachelor of Arts degree. He earned his Master's degree and Doctorate in Economics from Harvard University in 1971 and 1974 respectively.
From 1974 to 1984, Clarke held a number of senior positions in the federal government.
In 1985, he joined Merrill Lynch, and three years later was appointed Chairman and Chief Executive Officer of Morgan Financial Corporation. In 1991, he joined Canada Trust Financial Services Inc. in 1991, where he became President and Chief Executive Officer.
Following TD's acquisition of Canada Trust Financial Services in February of 2000, Clarke joined TD Bank Group as Chairman and Chief Executive Officer of TD Canada Trust. In this role he oversaw the integration of the TD and Canada Trust banking operations. He was appointed President and Chief Operating officer of TD Bank Group on in July 2000, and became Group President and Chief Executive Officer of TD Bank Group on December 20, 2002.
- Bilderberg - steering committee member
- Meet our President & CEO, TD Bank Group, accessed 3 June 2012.