Intellectual capital is the driving force of the new era. Concepts, ideas and images–not things–are the real items of value in the new economy. Wealth is no longer vested in physical capital but rather in human imagination and creativity. A 2007 report concluded that as much as 75 percent of most organizations’ value and sources of revenue (or wealth) creation are in intangible assets, intellectual property, and proprietary competitive advantages’‘. One study reported that intangible assets such as trade secrets, which had comprised 17 percent of the total value of the S&P 500 companies in 1975, had grown to 68 percent of that value by 1995, and 81 percent by 2009. Like anything else, as information becomes valuable, it attracts thieves. By 1996, it was estimated that nearly $24 billion of corporate intellectual property was being stolen each year. Since the Economic Espionage Act (EEA) was enacted in 1996, it has steadily assumed a more important and visible role as a law enforcement tool. In enacting the EEA, Congress cited a 1995 survey in which nearly one-half of corporate respondents reported having experienced a trade secret theft. By 2011, the security firm McAfee reported that every company in every conceivable industry with significant size and valuable intellectual property and trade secrets has been compromised (or will be shortly) In 1999, then-Deputy Attorney General Eric Holder stated that because intellectual property theft was soaring, the Department of Justice had concluded that we must make these types of crime a major law enforcement priority, and promulgated the first, comprehensive inter-agency plan to combat the growing surge in the theft of intellectual property. In 2013, Holder reported that between 2000 and 2010, DOJ had secured well over 100 convictions in cases involving criminal trade secret thefts. This handbook is intended as a practical guide for prosecutors, defense lawyers and court system as the investigation and prosecution of economic espionage and trade secret theft assume a more central place in the U.S. criminal justice system.