This document summarizes a talk given by Alexandra Eveleigh on the emergence of participatory archives from 2007-2008. It discusses how participatory archives actively engage users in co-creating historical meaning by liberating archival practice from hierarchical structures. Success depends on attracting different types of participants, from seasoned researchers to newcomers, and providing a variety of intrinsic and extrinsic motivation types and tasks. Managing this spectrum of participation is key to challenging archival authority while upholding quality control.