The past is often mysterious. By analyzing firsthand accounts and primary documents, a fraction of the mystery becomes clearer. The Washington Papers assists this endeavor by collecting, editing and publishing all of George Washington’s documentary record from his colonial days to the week of his death. Many of the letters published in these carefully prepared volumes and modern electronic formats reside in the National Archives or Library of Congress. The project’s mission is to make largely inaccessible documents available to everyone to further an understanding of Washington, his numerous correspondents, and the time period that profoundly shaped subsequent American history. My principal work at the Washington Papers has involved compiling a thorough index for Volume 20 of the Presidential Series, which focuses on Washington’s presidency during 1796. This index guides scholars and students as they look for information on the people, places or topics related to their research. To be truly helpful, an index must be accurate and complete. I found most interesting subject entries such as “agriculture” or “slavery” that aid cultural historians seeking to understand the social aspects of this fascinating epoch. The subject entries open up the full panorama of American history, which is the goal of projects like the Washington Papers. Allowing researchers to explore mysteries through Washington’s documentary record makes possible elucidations of the past to answer pressing questions of the present and future.