Nallathamby Devasahayam started his engineering career in 1971 at the Indian Institute of Technology Madras (IIT/M), Chennai, India. He worked there in defense related research projects, microprocessor and computer labs. He also worked in the Regional Sophisticated Instrumentation Center of IIT/M, where he was in charge of development and maintenance of several sophisticated analytical and research spectroscopic instruments. In that center he also developed an X-Band Pulsed Electron Paramagnetic Resonance (EPR) spectrometer. During that period he also visited the laboratory of Prof. Dr. Arthur Schweiger, ETH Zurich to get in depth knowledge in Pulsed EPR techniques. With that, after more than two decades of experience at IIT/M, he joined in 1996 the Bio Physical Spectroscopy and Imaging Section of Radiation Biology Branch, CCR, NCI to develop the Radiofrequency (300 - 750 MHz) Pulsed EPR imaging system currently in use. His paper 'Parallel coil resonators for time-domain radiofrequency electron paramagnetic resonance imaging of biological objects' published in the Journal of Magnetic Resonance, January, 2000 is the first whole body mouse EPR image and was cited at the Cover page. Then onwards many software and hardware developments are being carried out to continuously improve the mouse imaging. To his credit he has eight patents in FT-EPR imaging techniques. Efforts are now under way to scale up the EPR Imaging techniques for human applications.