The development of quantum devices by nanoscopic control of constituents is expected to be one of the largest and most intriguing challenges of modern solid state physics. Among the degrees of freedom which allow exploiting most quantum phenomena are spins. Their long coherence and relaxation times make them of interest to any kind of quantum spin”tronics” from spin memories to quantum computing and ultrasensitive sensors. In well chosen and engineered environments spin state control and readout can be easy and robust even under ambient conditions. It is the aim of the present proposal to develop complex single spin systems from diamond defects and other dopant/host systems to a degree known hitherto only in atomic physics in terms of controllability and isolation from their environment. These systems should be used to investigate fundamental physical properties, e.g. the quantumness of solid state spins as well as their utilization in sensory devices.To this end spin defects should be implanted into ultrapure diamond materials with a spatial precision below 10nm. Their relaxation properties should be optimized to the ultimate (spin phonon interaction) limit and individual spin quantum states should be read out in a quantum non demolition-type measurement with highest possible fidelities. This on the one hand will allow the set up of versatile quantum arrays to e.g. study quantum many body physics. On the other hand such structures will yield sensors for magnetic and electric fields with unprecedented sensitivity and scale spatial resolution. Such devices might have revolutionary impact on imaging applications in various fields from materials’ investigation to bio sciences.