The path beyond the limits of regular computers, even the most powerful supercomputer, lies with the theory of quantum mechanics. Quantum computing promises to change the world, but how do quantum computers work, and how close are we to this fabled new approach to computation? Host Dr Alfredo Carpineti spoke with Professor Winfried Hensinger, Professor of Quantum Technology at the University of Sussex, to discuss why we need quantum computers, what they would be used for, and why it's taking so long to get them.