Electron paramagnetic resonance (EPR) is a powerful technique finding its applications in many scientific areas covering chemistry, biology, medicine, materials science, physics and others. EPR has an unprecedented selectivity but relatively low sensitivity compared to other spectroscopic techniques, which makes EPR (working in the microwave spectral region) impractical for low-spin-density materials, especially when the imaging mode for heterogeneous samples is needed. In the project we propose a qualitatively new approach into the EPR area. It builds upon the strong enhancement and subwavelength spatial resolution of magnetic sensing field provided by plasmonic effects based on collective oscillations of electrons at surfaces or in nanostructures. In contrast to usual THz plasmon-enhanced spectroscopy of nonmagnetic materials, we build upon magnetic plasmonic resonances. This presents unprecedented implementation of plasmonic phenomena into EPR technique. Plasmon-enhanced Terahertz Electron Paramagnetic Resonance (PE THz EPR) spectroscopy and scanning microscopy is developed as a radically novel method for the local analysis of paramagnetic organic and inorganic species and materials with significantly enhanced sensitivity (by four orders of magnitude) and unprecedented spatial resolution. Such a significant enhancement of the EPR performance will for instance open new ways in magnetic sensing technologies enabling to study in situ functional centres in a wide variety of materials, and, generally, trigger the development of the EPR-employing industry.