In recognition of the rise of mobile computing, a collection of articles is presented to explore its transformative influence on libraries, librarians and library services. Libraries are offering an expanding array of electronic resources, and patrons are eager to access them on their smartphones, tablet, and similar devices. Despite technological and budgetary challenges, librarians are finding success through creativity and collaboration. This special section explores several aspects of mobile computing in the library context. The articles describe innovative projects made possible by partnering with experts offering programming and other skills, technology implementations that expand users’ awareness of and access to resources and practical solutions to common challenges of mobile sites for libraries.