The European Medicines Agency (EMA) has recently published guidelines for the evaluation of medicinal products for the treatment of Duchenne and Becker muscular dystrophies (DMD and BMD). The document, which is open access, is currently available for consultation until 31 August 2013. Duchenne and Becker muscular dystrophies are rare diseases, and while DMD is a life-threatening disease that significantly reduces the life expectancy of sufferers, BMD patients have a longer life expectancy. Recent advances in basic and clinical research have opened up prospects for new treatment options for DMD and BMD, leading to an increase in clinical trials. Guidelines published by the EMA have been drafted in view of these new developments, providing information and recommendations on clinical strategies to be adopted. The EMA acknowledges that "due to the heterogeneity of the phenotypes of both diseases and the expected outcomes that may also vary depending on the stage of the disease", it is not possible to provide clear and comprehensive guidance and, therefore, "this document should be considered as general guidance and integrated with other relevant guidance provided by the EMA and the ICH".