This essay is the winner of the 2012 Jean Arnot Memorial Fellowship. The essay draws on Rose Holley's experience of managing innovative library services that engage crowds such as The Australian Newspapers Digitisation Program and Trove, and her ongoing research into library, archive and museum crowdsourcing projects. This experience and knowledge has been put into the context of Jean Arnot’s values and visions for Australian libraries. Jean Arnot, the distinguished Australian librarian, described her vision for an innovative library service over sixty years ago. Rose suggests how some of her goals are now being achieved through use of the internet and digital technologies, and how we can build on these to ensure that libraries remain valued and relevant by harnessing the cognitive surplus of the nation they serve, and by crowdsourcing