This handbook aims to provide updated information on the current progress of biosimilar medicines in the European Union (EU). The first edition of this short guide to biosimilar medicines was published in 2007. At the time of first publication, only 5 biosimilar medicines had been approved in Europe, and both the legislation and concepts for these products were very new. Now the situation has developed and changed, as will be described herein, and the clinical and health economic benefits offered by biosimilar medicines to patients, clinicians and healthcare providers are considerably clearer.