Ms. O’Neill is a Corporate Director and has extensive experience in accounting and financial services. Previously, she was an Executive Vice-President of the Bank of Montreal (BMO) Financial Group with accountability for a number of major business units. Prior to joining BMO Financial Group in 1994, she was a partner with PricewaterhouseCoopers. Ms. O'Neill is an FCA (Fellow of Institute of Chartered Accountants) and has an ICD.D designation from the Institute of Corporate Directors. Ms. O'Neill was a member of the Steering Committee on Enhancing Audit Quality sponsored by the Canadian Institute of Chartered Accountants and the Canadian Public Accountability Board. In 2014, Ms. O’Neill was awarded Canada's Most Powerful Women: Top 100 Award by the Women's Executive Network.
Ms. O'Neill currently serves as the Chair of the audit committee for Invesco Canada Funds, Cadillac Fairview Corporation Ltd. and Finning International Inc., the world’s largest Caterpillar dealer. Ms. O’Neill is the past Chair of St Joseph’s Health Centre and St Joseph’s Health Centre Foundation of Toronto. She has been a director of ARC since 2009.