After the National Counterintelligence Center designed and conducted several iterations of a seminar on The Evolution of American Counterintelligence, it became apparent that a well-thought out reader would be ideal to complement the lectures. We concluded that the great abundance of literature on counterintelligence and intelligence is, ironically, one of the main obstacles to understanding our discipline. Most of the current books and articles concern the numerous espionage cases that have plagued our profession over the past few years. The more famous, or infamous, the spy, the more books written. Only a few books endeavored to scrutinize counterintelligence but the treatment was uneven.

Our reader's three volumes cover counterintelligence's past and present. Nevertheless they form a whole: the first volume provides material elucidating counterintelligence's antecedents from the American Revolution to World War II. Volume two focuses on World War II while volume three begins with the Atom Bomb spies and concludes with the latest espionage cases. History is more than background; it is the framework of the present.

We have taken material from official government documents, indictments from several espionage cases, and articles written by professors, scholars and counterintelligence officers. We have abridged some selections while trying not to change the sense of the original but we have not altered the original usage of the English language.

Each chapter in the three volumes has an introduction, which sketches out the main trends and characteristics of the period in question. There is a chronology with each chapter for volumes one and three, but volume two only has one chronology to cover the entire period. At the end of each chapter is a selected bibliography. We hope this will help you get a sense of the period as a whole. The reader is not all-inclusive and people may disagree with our selections, but at least we hope to have provided sufficient material to entice our colleagues to do further research.

Counterintelligence is a fascinating and challenging discipline. Our response to these challenges is determined, not by the requisites of the immediate situation but by our historical legacy. Thus we urge that the materials presented in the three volumes be read, not as background to the present, but as part of the present itself.