Up until fairly recently, library collections have consisted of physical things--books; journals; audiovisual materials; and, in some libraries, collections of realia. Now, however, collections often include materials that cannot be placed on library shelves either because they are digitized versions of primary sources or because they exist only in electronic form and do not have physical counterparts. These digital materials need to be organized and managed just as physical materials do, not only so we can handle the details of licensing, subscriptions, rights management, and other acquisitions issues, but also so patrons can retrieve them just as easily as if they were housed on library shelves. In this column, the author describes digital asset management projects at WGBH (the Boston affiliate of the Public Broadcasting Service) and at the University of Michigan. She also did discusses the issues of digital rights management (DRM) and electronic resource management (ERM).