First came the switch. Then the transistor. Now another innovation stands to revolutionize the way we control the flow of electrons through a circuit: vanadium dioxide (VO2). A key characteristic of this compound is that it behaves as an insulator at room temperature but as a conductor at temperatures above 68°C. This behavior – also known as metal-insulator transition – is being studied in an ambitious EU Horizon 2020 project called Phase-Change Switch. EPFL was chosen to coordinate the project following a challenging selection process.