Using the example of New Walk Museum, Leicester, and its collections, the complexity, multi-causality, and reasons for change in museums are examined and explained. The 170 years history of New Walk provides an original basis and innovative approach to be adopted towards explaining museum change. The book makes use of original interview and archive material to examine how and why social, economic, political, and professional developments affected the work that was undertaken in New Walk. The time-span covered is much longer than is normal for a book on museum history and is longer than for almost all the national museums in the UK, with this allowing for a nuanced understanding of the causes and consequences of museum change over time. The problems and possibilities of undertaking museum history research are also discussed. Detailed examination of the ways in which a variety of societal developments fed into museum change is a key feature of the book. The book is aimed at all those with an interest in understanding how and why change affects museum practice and will be of interest to museum professionals, academics, and students in museum studies, history, politics, and sociology as well to the general museum visitor who would like to discover more about the institutions that they visit.