Driven by advances in technology and experimental capability, the last decade has seen the emergence of quantum technology: a new praxis for controlling the quantum world. It is now possible to engineer complex, multi-component systems that merge the once distinct fields of quantum optics and condensed matter physics.EPJ Quantum Technology covers theoretical and experimental advances in subjects including but not limited to the following:Quantum measurement, metrology and lithographyQuantum complex systems, networks and cellular automataQuantum electromechanical systemsQuantum optomechanical systemsQuantum machines, engineering and nanoroboticsQuantum control theoryQuantum information, communication and computationQuantum thermodynamicsQuantum metamaterialsThe effect of Casimir forces on micro- and nano-electromechanical systemsQuantum biologyQuantum sensingHybrid quantum systemsQuantum simulations.