The scientific and technological legacy of the 20th century includes milestones such as quantum mechanics and pioneering spac ... e missions. Both endeavours have opened new avenues for the furthering of our understanding of Nature, and are true landmarks of modern science. Quantum theory and space science form building blocks of a powerful research framework for exploring the boundaries of modern physics through the unique working conditions offered by experimental tests performed in space. Space-based sources of entangled photons promise the formation of global quantum communication networks, long-distance tests of quantum theory and the interplay between relativity and quantum entanglement. Long free-fall times enable high-precision tests of general relativity and tests of the equivalence principle for quantum systems. Harnessing microgravity, high vacuum and low temperature of deep space promises allowing the study of deviations from standard quantum theory for high-mass test particles. Space-based experiments of metrology and sensing will push the precision of clocks, mass detectors and transducers towards the engineering of novel quantum technologies. Such an exciting framework is what “Quantum Technologies in Space (QTSpace)” aims at providing. QTSpace will embody a visionary opportunity for furthering the comprehension of fundamental mechanisms of physics in an entirely new context. read more