The second edition of Reference and Information Services in the 21st Century: An Introduction updates and expands on the excellent foundation provided in the first edition and continues to ground the reader in real-world practices. In this new edition, editors Kay Ann Cassell and Uma Hiremath account for the changing nature of reference services by including an entirely new chapter on Reference 2.0 tools. They have also thoroughly updated the book's chapters, weeding some sources and including new ones. Guided by an editorial advisory board of university educators and practitioners, this text expertly combines both practical elements and guiding principles, and it is sure to be useful to students and novice and experienced reference professionals seeking a core reference text, as well as educators in the field of library and information studies. The book is arranged into four major parts: fundamental concepts, an introduction to major reference sources, special topics in reference and information work, and development and management of reference collections and services. Part I includes chapters that introduce the reader to the basics of reference and information services, the reference interview, and basic search techniques to find the answer. Part II includes chapters on answering a variety of questions—from questions that require handy facts to questions about events and issues—and pairs that with the sources that would best accommodate the question at hand. Part III includes chapters on when and how to use the Internet as a reference tool, reader's advisory work, reference work with children and young adults, and information literacy in the reference department. Part IV includes chapters on selection and evaluation of reference materials, management of reference departments, assessment and improvement of reference services, Reference 2.0, and the future of information services. This edition has also added an appendix that includes the Reference and User Services Association's Outstanding Reference Resources from 2005 to 2009. Additionally, efforts will be made to keep the book up-to-date, as the authors will supply information to a companion website, hosted by the publisher. This web page will feature new readings for each chapter and information about changes in the reference tools described as well as important new tools that may come along post publication. One of the strengths of this book is that it is grounded in real-world practices. The newest chapter on Reference 2.0 is no exception as it introduces the reader to Web 2.0 tools and their practical application in libraries. While the goal of reference is timeless (“namely, the satisfaction of the user”), the authors explain that Web 2.0 tools have added a new dimension to reference services. In particular, the reference professional must acknowledge a change in users' expectations: chiefly, that users have come to expect that the information they receive has been individually tailored, “so that the uniqueness of the users' needs are both acknowledged and satisfied.” The chapter explains what is meant by “Reference 2.0,” namely, collaboration (e.g., cooperative content creation via wikis, blogs, folksonomies, etc.), social networking (e.g., reference outreach via Facebook), customization (e.g. really simple syndication [RSS] feeds), and seamlessness (e.g., multi-format reference via instant messaging). Most importantly, the Reference 2.0 chapter proceeds to delve into specific, real-world examples of collaborative content creation, such as reference wikis and blogs; reference folksonomies, such as libraries' use of Delicious; social networking; customization, such as search widgets, reference RSS feeds, and mashups; and seamlessness, such as mobile reference. The authors recognize that some of this technology may not last and that it is easy to get caught up in the glitter of “shiny new toys.” However, they emphasize that it is not possible to pretend that it is not happening and that it is good behavior for the reference professional to get “intimate with the arsenal of tools available.” This book is highly recommended for all individuals seeking a core reference services text. It will be useful not only for students and new reference librarians, but also for seasoned reference librarians to be aware of the latest tools and resources.