Martin's practice focuses on tax planning and tax litigation. 

On the planning side, he has particular expertise in corporate and international tax planning, debt financing transactions and foreign entities carrying on business in Canada.
Martin also represents both individual and corporate clients on federal and provincial tax litigation matters, including disputes under the Excise Tax Act, the Income Tax Act, the Land Transfer Tax Act and the Employer Health Tax Act.

Martin is a former chair of the Ontario Bar Association (Tax Section) and is a member of the Board of Governors and the Executive Committee of the Canadian Tax Foundation.  He is also a member of the International Fiscal Association and the Advocates' Society. To complement his practice, he has completed the Canadian Institute of Chartered Accountants In-Depth Tax Course.

Martin has also taught corporate taxation at the Queen's University Faculty of Law and Osgoode Hall Law School, and is a contributing editor to Taxation of Corporations, Partnerships and Trusts, 5th Edition (Thomson Reuters) (with the 6th Edition to be released in early 2022).