Imagine having a digital twin that gets ill, and can be experimented on to identify the best possible treatment, without you having to go near a pill or a surgeon's knife. Scientists believe that within five to 10 years, "in silico" trials – in which hundreds of virtual organs are used to assess the safety and efficacy of drugs – could become routine, while patient-specific organ models could be used to personalise treatment and avoid medical complications. Digital twins are computational models of physical objects or processes, updated using data from their real-world counterparts. Within medicine, this means combining vast amounts of data about the workings of genes, proteins, cells and whole-body systems with patients' personal data to create virtual models of their organs – and eventually, potentially their entire body. "If you practise medicine today, a lot of it isn't very scientific," said Prof Peter Coveney, the director of the Centre for Computational Science at University College London and co-author of Virtual You.