This document summarizes the goals and activities of the "Hidden Collections" Processing Project. The project aims to process approximately 200 collections across 23 repositories in the Philadelphia area to make them accessible online. Student processors are minimally processing collections at a rate of 2 hours per linear foot to create standardized finding aids in the Archivists' Toolkit database. The project has faced challenges with time constraints and developing consistent standards, but has succeeded in making many previously inaccessible collections available to researchers.