My main research interests focus on high-energy observations of Active Galactic Nuclei (AGN). I have recently used X-ray observations of nearby AGNt galaxies to study: a) the ionization mechanism of the Narrow Line Regions; b) the evolution of the AGN activity and environment in the late stages of gelaxy mergers, using data of X-ray observatories (primarily XMM-Newton). Bright times are coming for AGN science, with the unprecedented spectroscopic capabilities of the micro-calorimeters on board XRISM and Athena to become operational during the next decade. I am involved in the preparation of future missions as Project Scientist of the ESA contribution to XRISM, and Study Scientist for NewAthena.