The subtitle of this volume is ‘From margin to mainstream’. The chapters included here are indeed testament to the extent to which M-Libraries has moved since the publication of the first volume in 2008. While the use of mobile technologies by libraries is not exactly commonplace, an ever-increasing number of libraries have mobile websites, and the range of innovative projects described here is impressive. It is an area where one size definitely does not fit all and libraries are adopting and adapting the technologies to fit their specialist needs and priorities. For some this will be the use of QR codes to help users physically locate items in a vast area of shelving. For others, the use of SMS messaging will address the need to find a quick and effective way of communicating with a geographically dispersed user population, or the use of iPads will free reference librarians from their enquiry desks. In summary, this volume serves to demonstrate the ability of libraries and librarians to identify creative ways of harnessing technology to address problems and to meet the increasingly sophisticated expectations of their users and to continue to provide quality service and information to their users.