Library Value May Be Proven, If Not Self-Evident Guest Editor, Martha Kyrillidou, Senior Director, Statistics and Service Quality Programs, ARL W e hold these truths to be self-evident: libraries are valuable to humankind libraries preserve knowledge libraries enable access to information libraries serve the information needs of their users. To the believer the truth is evident. But libraries are not natural phenomena like the sun rising and setting every day. Libraries are institutions created and supported by those individuals who hold that these statements are true even if not self-evident to everyone. The caretakers of libraries have gathered data on library performance for decades and have used this information to understand how to improve services and programs they provide to their users. The ability to measure the quality of library services is extremely important as libraries are faced with the need to make informed decisions about the best way to meet the needs of the users of those services. This ability has become even more important as libraries make transformative changes during times of fiscal constraint and increased competition. ARL has built a program of assessment over the past 20 years and continuously looks for ways to strengthen this capacity for member libraries. This issue of RLI highlights ways in which assessment tools have helped libraries improve their services and programs. These improvements are the result of library leadership and their staff using data to make decisions that would have the most impact. This issue also captures some of the newer initiatives focused on demonstrating the value of library services. LibQUAL+® has now been used for a decade by upwards of 1,200 libraries around the world in 20 language versions. The results have helped libraries understand users’ perceptions of library service quality. Colleen Cook and Michael Maciel provide a brief historical look at the evolution of LibQUAL+® and highlight how the administration of this tool enabled the Texas A&M University Libraries to make significant service improvements based on sound data. The RLI 271 1 AUGUST 2010 RESEARCH LIBRARY ISSUES: A BIMONTHLY REPORT FROM ARL, CNI, AND SPARC