The purpose of this study is to identify and compare international anti-terrorism legislation which occurred as a direct result of the terrorist attacks on September 11, 2001. More specifically, the study identifies anti-terror legislation which was passed in various countries, each with different legal traditions, and analyzes the comparisons. The study includes the five major legal traditions. Only of the countries subject to the selection for analysis is on the United States' "State Sponsor of Terror" list. All other nations are allied states in the Global War on Terror. This thesis finds that certain nations were more active in passing legislation, certain nations passed no legislation immediately attributable to 9/11, and anti-terrorism legislation in different nations have similar topics despite political differences. Additionally, this thesis discovered that anti-terrorism legislation greatly varies from nation to nation. The implications are that September 11, 2001, caused nations from all legal traditions to examine the weaknesses in their nations' legislation and pursue efforts to eliminate them.