Investigation Library
The Central Archive
One Library. Free Investigator Membership.
The Eftsona Investigation Library is the central home of our evidence-based Investigation Files and institutional publications.
Every file is researched, documented, and organized to help readers examine evidence rather than rely on assumptions. Collections are arranged by subject and investigation number so that the Library remains consistent as it grows.
Every Investigator member can access the full investigation library, including investigations previously listed under Researcher and Archivist.
Read an Investigation
Browse Investigations by Subject
Choose a subject collection below, then select an investigation to read. All collections are included with free Investigator membership.
Ancient World
Historical Investigations
Nature & Science
Society
Technology & Engineering
The Library Doors
Explore the Library
Join Eftsona for free, then explore investigations, Deep Dives, and library publications.
Investigation Atlas
Explore the investigation catalog across all five subject collections. Search by topic and find your next investigation.
Explore the AtlasDeep Dive Investigations
Follow the evidence further with extended investigations. All Deep Dives are included with free Investigator membership.
Explore Deep DivesLibrary Publications
Read the library's monthly research journals and quarterly collections.
Monthly Journals Quarterly CollectionsA Permanent Structure
How the Library Is Organized
The library is organized into five subject collections. Within each collection, Investigation Files are identified by category code and investigation number.
This structure allows new work to be added without changing how readers navigate the Library. Eftsona will continue to add investigations as they are completed and brought to the appropriate institutional standard.
Separate Institutional Functions
Library Membership and Academy Enrollment
The Investigation Library and Eftsona Academy serve different purposes.
Library Membership
Free Investigator membership provides access to the investigation library and its member publications.
Academy Enrollment
Governs investigative training, coursework, examinations, and Eftsona-issued certificates of completion or standing.
Academy enrollment and Bookshop purchases are separate from free library membership.
Continue the Inquiry
Enter the Library
Create your free Investigator account to begin exploring, or sign in with your existing Eftsona account.
Question Everything.Where Inquiry Begins Again.