The book will look at issues related to the stepped wedge randomised controlled trials design. This is a design that is being increasingly used in the evaluation of interventions/programmes as it allows for all units to receive the intervention by the end of the study. The book will provide a state of the art reference for those interested in using the design. It will include an introduction to the background and history of the design and an updated review of existing studies. The book will cover methods of randomisation and sample size calculations and the implications of the number of steps and number of clusters on these. Approaches to the analysis of the design will also be covered focusing on the appropriate methods for the different outcomes.Examples of challenges in using the design will be explored. Issues in presentation and reporting of the design will be visited. The book will also discuss how health economics can be integrated within the design.