A general lack of experimental data on the crystal structure and local distortions in High Entropy Alloys (HEAs), all factors considered crucial for the understanding of mechanical properties, emerges from the latest reviews. This project plans to directly tackle some of these aspects on a so-called Senkov alloy based on Ti-Zr-Nb-Hf-Ta. We plan to investigate by means of X-ray absorption Spectroscopy the HEA together with its binary and ternary precursors thus investigating the role of each element and correlate it to the Senkov “mother” alloy. The Senkov alloy family was chosen because it is the most studied in literature from the mechanical properties point of view, but detailed structural information at the atomic scale are still missing. The results will be then related to i) mechanical properties (to be measured on the same compounds and integrated with the literature), and ii) on-going crystal structure investigation on similar hcp-based and fcc-based high entropy alloys.