Within a context of recent and rapid transformation in authorship and participation practices on the Internet, this thesis explores the implications of an emerging digital culture for heritage institutions, such as museums and archives. Combining insights from internet, education and museum theory it explores different experiences of participation and meaning making around digital heritage collections opened to public engagement and contribution. In particular, the investigation analyses and contrasts the online activities of the Royal Commission on the Ancient and Historical Monuments of Scotland (RCAHMS), partner in the research, with alternative approaches. The thesis applies ethnographic research methods to investigate embodied and virtual settings. Based on the empirical findings, it identifies different theoretical models of online engagement with heritage content. It then extrapolates from these models a conceptual framework that could be used by heritage institutions to analyse and re-assess their online practices, intellectual positioning and strategic ambitions in the context of the paradigm shift brought about by digitality.