2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/8766I present some recent developments on high-energy phenomena in YSOs, concentrating on the new evidence for accretion-induced X-ray emission in YSOs, for Fe 6.4 keV fluorescent emission from the disks of YSOs and for very long magnetic structures responsible for intense X-ray flares, likely connecting the star and the circumstellar disk.Proceedings of a conference on 'Low-mass stars and brown dwarfs: IMF, accretion and activity' held in Volterra (Italy) in October 2004 (Memorie della Societa` Astronomica Italiana)Astrophysicstext