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Margaret R O'Sullivan

Margaret R O'Sullivan
T-D Centre, Suite 3430
TD Bank Tower
66 Wellington Street West
PO Box 68
M5K 1E7
+1 416 363 3700
+1 416 363 9570


Who's Who Legal Private Client: Lawyers

Margaret O'Sullivan's practice involves all aspects of private client work, including estate planning; will and trust planning; incapacity planning; estate litigation; advising executors, trustees and beneficiaries; and administration of estates and trusts. Margaret is recognised in The Best Lawyers in Canada (2017) and the 2016 edition of The Canadian Legal Lexpert Directory as a leading practitioner in estate planning; and in Who’s Who Legal: Private Client (2016) and Who’s Who Legal: Canada (2016) as one of the most highly regarded private client practitioners. She is a top ranked private client lawyer in Chambers Canada 2016 and a top ranked private wealth lawyer in Chambers High Net Worth (2016), and is the recipient of the 2014 STEP Founder’s Award for Outstanding Achievement and the Ontario Bar Association’s 2013 Award of Excellence in Trusts and Estates Law. Prior to establishing an independent practice, Margaret was a partner in the Toronto office of the national Canadian law firm Stikeman Elliott, where she directed its trusts and estates practice. She has practiced exclusively in the area of trusts and estates since 1983.

Margaret is a founding member and a former deputy chair of the Society of Trust and Estate Practitioners (Canada) and former chair of the editorial board of its newsletter STEP INSIDE. She is a former deputy chair and former member of the board of directors and council for STEP Worldwide, as well as a former chair of the professional standards committee. She is a former chair of the trusts and estates section of the Ontario Bar Association, and a past elected member of the Ontario Bar Association Council (1993–98). She is a current member of the Canadian Bar Association, the American Bar Association, the New York State Bar Association, the International Bar Association, the Canadian Tax Foundation, as well as an academician of The International Academy of Estate and Trust Law. She was elected a fellow of the American College of Trust and Estate Counsel in 1995. Margaret is also a member of the Queen’s University Gift Planning Advisory Committee.

Margaret has been a frequent guest speaker, writer and conference chairperson for various professional organisations on the subject of trusts and estates, including for the Society of Trust and Estate Practitioners, the Canadian Bar Association, The Law Society of Upper Canada, the International Bar Association, the Canadian Tax Foundation and various private conference sponsors. She has also written extensively in the areas of trusts, estate planning, estate administration and estate litigation. She is past editor and contributor to the Ontario Bar Association’s trusts and estates section newsletter. Margaret authored two textbooks and developed the courses “Engineering of a Trust” and “Trust and Estate Management” for the Trust Institute of the Institute of Canadian Bankers. She is a co-author of the Canada chapter in International Succession Laws (Tottel 2009), and a contributing author to Widdifield on Executors and Trustees (Carswell 2002), The Private Wealth & Private Client Review (Law Business Research 2015), The International Comparative Legal Guide to: Private Client 2016 (Global Legal Group 2015), Private Client Multi-jurisdictional Guide 2015/16 (Practical Law Company) and Lexis Practice Advisor Canada (LexisNexis). 

WWL says: Margaret O’Sullivan is “great with clients”. She is one of the leading trust and estate lawyers in Canada.

This biography is an extract from Who's Who Legal: Private Client which can be purchased from our Shop.

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87 Lancaster Road, London
W11 1QQ, UK