Not long after the September 11 attacks, I had a conversation with a Pakistani entrepreneur. This businessman could be charitably described as being involved in international gray markets and illicit finance. We discussed many of the subjects addressed in this book, including trade-based money laundering, value transfer, hawala, fictitious invoicing, and countervaluation. At the end of the discussion, he looked at me and said, “Mr. John, don’t you know that your adversaries are transferring money and value right under your noses? But the West doesn’t see it. Your enemies are laughing at you.” The conversation made a profound impact on me. I knew he was right. Spending the better part of a career as a special agent with the U.S. Customs Service, I conducted investigations both in the United States and overseas. Over the years, I developed sources and expertise in many of the indigenous, ethnic-based, underground financial systems that are found around the world. I knew firsthand that the common denominator in many of these underground financial systems was trade-based value transfer.