International taxation is the branch of tax law that deals with the tax implications of cross-border transactions and activities. It encompasses the rules and regulations that govern how countries tax individuals, businesses, and transactions that occur across national borders.
Key principles of international taxation include residence-based taxation, where individuals and businesses are taxed based on their residency status, and source-based taxation, where income is taxed in the country where it is earned. Double taxation, which occurs when the same income is taxed by more than one country, is a significant concern in international taxation. To mitigate this, countries often negotiate tax treaties that allocate taxing rights and provide mechanisms to relieve double taxation.