The Now and Then community heritage wiki was initiated to research the potential of Web 2.0 technologies to engage and sustain interest in local history and heritage collections. The aim of this action research project is to explore whether wikis can provide a low-cost, sustainable way of increasing interest and participation in the preservation, interpretation and enjoyment of local history and heritage collections. The target organisations to use the wiki are generally very small and are often staffed solely by volunteers. The pilot implementation in a small rural community has been well received and is generating significant levels of interest and participation. This paper aims to share the learning from this project about the potential and implications of wikis as the basis for sustainable knowledge communities around local history and heritage. It explores how collaborative knowledge-making practices such as crowdsourcing present new challenges and opportunities for museums, their information management paradigms, and their relationships with communities.