Biosimilars are highly similar versions of originator biological medicines, which are approved according to the same standards of pharmaceutical quality and have comparable efficacy and safety in patients. Biosimilars offer important benefits to society as their market introduction has been shown to reduce costs and increase patient access to important and often expensive biological therapies. Currently, biological medicines account for approximately 40% of total pharmaceutical expenditure in Europe, and this share is projected to further rise over coming years. As such, the introduction of biosimilars to the market is an essential and necessary way to manage this growing segment and improve the affordability and accessibility of biological medicines for patients and our healthcare systems. Here, Barbier and Vulto discuss the challenging factors for the adoption of innovations in medicine, and biosimilars in particular.