Commodity taxation is generally understood to encompass matters concerning the federal goods and services tax ("GST"), various provincial sales taxes, customs and excise issues, and related matters involving the domestic and international supply of property and services. Given the degree of specialization involved in their practise, commodity tax lawyers often engage in all aspects of commodity tax work, from the solicitor-type work involved in the planning stage, to litigation work as matters progress from the level of administrative review, to the federal and provincial courts of first instance, and on to the Courts of Appeal and beyond.