Service design is a holistic, co-creative, and user-centered approach to understanding user behavior for creating or refining services. Use this LITA Guide to help as a toolkit for implementing service design studies and projects at all types of libraries. It begins with directions for how to create a service design team and assembling a user working group for your library and move through the various phases in a service design journey. The authors outline the tools required to gain insights into user behavior and expectation and how to diagnose the difference between a symptom and a problem users face when interacting within the library environment. The guide features a series of examples that the service design team can use to learn how to work with library staff and patrons to find out what current user experience is like and how to refine services to better meet user expectations.