The main field of research of Valentina D’Odorico is observational extragalactic astrophysics. She investigates the formation and evolution of cosmic structures through the properties of the gas diffused between and inside galaxies. This low density gas is mainly detected in absorption against the spectrum of bright background sources, in particular quasars. Valentina D’Odorico is interested in the metal enrichment of the intergalactic gas, as a probe of both galaxy evolution and the reionization process. She has been leading several large observational programmes to collect samples of high resolution quasar spectra with state-of-the-art spectroscopic facilities. These samples (XQ-100, XQR-30, EQUALS) together with new ones will be exploited to reach the objectives of RECAP. She is also deeply involved in the development of future high-resolution spectrographs: CUBES at the VLT and ANDES at the ELT.