About HDM Law

HDM Law is a solo law practice run by lawyer Heather Marshall out of an office in Thornhill, in York Region just north of Toronto. The practice serves clients in Vaughan, Markham, and Toronto, and focuses on three areas: wills, estates and trusts, real estate, and commercial leasing. Marshall earned a Bachelor of Laws from Osgoode Hall Law School in 2007 and won the Dominic Carinci Memorial Prize for achievement in real estate and business associations while there. Marshall was called to the Bar of Ontario in 2008, after articling at a downtown Toronto firm, and worked at a mid-sized full-service firm in North York and a large downtown firm before opening an independent practice.

The estate planning side of the practice includes training beyond the required minimum. In 2019, Marshall completed the Osgoode Professional Development Intensive Program in Wills and Estates. The leasing practice has a published component too, since Marshall co-authored a chapter in Shopping Centre Leases (2nd Edition), a reference text used in the field. HDM Law describes its approach as personalized, timely, and cost-effective, with advice meant to be practical and understandable rather than dense with jargon. The office relocated in October 2019 to its current location at Yonge and John in Thornhill.

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Where to find them

7636 Yonge Street, Thornhill, Ontario L4J 1V9 · 416-800-7349

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This listing was generated by AI from public sources in September 2026. It may contain errors, and we can’t guarantee it’s accurate or complete. Before you rely on anything here, verify it on the firm’s own website. Verify licence status in the Law Society of Ontario directory ↗

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