This handbook is designed to show that Section 337 investigations are an underutilized tool that should be in every IP practitioner's toolkit. Section 337 of the Tariff Act of 1930 prohibits unfair competition related to the importation of products into the United States that infringe valid U.S. patents, copyrights, trademarks or embody a misappropriated trade secret. The United States International Trade Commission (ITC) is a federal agency that provides trade expertise to the government and oversees Section 337 investigations and proceedings. This timely handbook offers a guide to the intricacies of Section 337 procedure and demystifies the ITC as a legal venue in an effort to help practitioners select the optimal forum for their clients' cases. Both authors are seasoned attorneys who practice Section 337 litigation before the ITC, U.S. district courts and circuit courts of appeals, bringing a wealth of experience and guidance to the reader.