In the early '40s, rumors about World War II began to spread throughout the United States. The U.S. government was worried about the possible dangers of these rumors and the adverse effects that they could have on American society. The U.S.A. entered World War II on December 8, 1941, and to fight rumors dangerous to national security, the U.S. government decided to encourage social scientists to study the phenomenon of rumors. After the war, Allport and Postman published The Psychology of Rumor (1947). This study was a breakthrough in social psychology. Allport and Postman (1947) defined rumors as propositions of faith on specific (or current) topics that pass from person to person, usually by word of mouth, without evidence of their truth. We have republished, as a facsimile edition, Allport's original work of 1947. This book has been formatted from its original version for publication. IMPORTANT, although we have attempted to maintain the integrity of this title accurately, the present reproduction could have minor errors due to the age of the original scanned copy.