2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/140712The imaging capabilities of the INTEGRAL and HESS observatories allow the study of hard X-ray and TeV sources with unprecedented positional accuracy. Here I review the multiwavelength followup studies which are currently being performed on the unidentified sources detected by these facilities in order to unveil their actual nature.11 pages, 6 figures, ChJAA in press; proceedings of the Frascati Workshop 2007 "Multifrequency behaviour of high energy cosmic sources" (F. Giovannelli & L. Sabau-Graziati eds.). The quality of Fig. 1 was degraded to fit the arXiv uploads size limitsAstrophysicstext