The acute onset of orbital and periorbital inflammation presents the clinician with a diagnostic and therapeutic dilemma, the consequence of which may be very serious. The progression from the initial stage of cellulitis to orbital abscess, cavernous sinus thrombosis, brain abscess, meningitis, or visual loss may be quite rapid at times. CT, ultrasonography, and MR imaging play an important role in clinical management of these patients. Indeed, it is the information obtained through orbital imaging that directs the clinician to use the correct therapeutic modality.