Librarians, like patrons and researchers, are caught between traditional library service models and the promise of evolving information technologies. In recent years, professional conferences have strategically featured programs and presentations geared toward building a mobile agenda and adapting or adopting services to meet new demands of mobile users. Yet for every librarian with a mobile success story, there are many more seeking to identify how, when, and why to develop mobile library services. Adding to the complexities of the mobile puzzle, even vanguard libraries report relatively little overall usage of mobile services. So while mobile interest and capabilities are increasing, libraries with taut budgets must carefully weigh the benefits of specialized services with the costs of delivery. To set a baseline on the extent of current mobile services and to identify desired features, "Library Journal" recently conducted an email survey of public and academic libraries. Results from the 483 respondents indicate that many libraries are endeavoring to participate in the mobile environment, either by implementing or planning to implement mobile services. Overall, 44% of academic libraries and 34% of public libraries currently offer some type of mobile services to their customers; two out of five libraries of all types, academic and public, report plans to "go mobile" in the near future.