Rare diseases affect up to 36 million people in the EU, but often no treatment options are available. The ideas and early stages of development of therapies for rare diseases often originate from academic institutions. But further development often stagnates. This may be due to the complexity of the disease, small patient populations of predominantly young children, high risks for industry with limited options for reimbursement, regulatory challenges and high costs for society. In this session will be highlighted how modelling can contribute to the development of therapies for rare diseases