2021 Reprint of 1999 Edition. Full facsimile of the original edition. Not reproduced with Optical Recognition software. This volume pulls together and republishes, with some editing, updating, and additions, articles written during 1978-86 for internal use within the CIA Directorate of Intelligence. The information is relatively timeless and still relevant to the never-ending quest for better analysis. The articles are based on reviewing cognitive psychology literature concerning how people process information to make judgments on incomplete and ambiguous information. The essays selected are the most relevant to intelligence analysis and most in need of communication to intelligence analysts. The articles are intended to help the intelligence analysts understand and interpreted the issues that most intelligence analysts face.