The ‘Voice of the Volunteers’ workshop was designed to hear directly from volunteers who had taken part in online cultural heritage citizen research projects. We wanted to hear about their motivations, experience and preferences. We also used the workshop as an opportunity to elicit feedback on the newly launched indexing tool, which allows volunteers taking part in Zooniverse projects to choose their own pathway through a set of records. This workshop was part of a series of workshops within the project Engaging Crowds: citizen research and heritage data at scale, a collaboration between The National Archives, the Royal Botanic Garden Edinburgh, Royal Museums Greenwich and Zooniverse at the University of Oxford. Engaging Crowds is a Foundation Project within the Arts and Humanities Research Council-funded Towards a National Collection programme.