Through a historical analysis of the link between Italian American migration in the 20th century and the investigation of the minutes of the Board of Directors and the financial statements of the American Chamber of Commerce in Italy, this book provides a privileged observation point for the study of the economic relations between Italy and the United States throughout the twentieth century. Showing that the Chamber played a fundamental role in highlighting the changes of Italian economy and society, and in strengthening the cooperation between the two countries, it retraces a long-lasting tradition of trade and business, and depicts a solid and enduring relationship between Italy and the United States.