Seven patients with orbital complications of sinus surgery seen over a 10-year period are reported. Severe intraoperative orbital hemorrhage occurred in three patients while undergoing external or intranasal ethmoidectomy. In one patient, an avulsed anterior ethmoidal artery was identified as the source of bleeding, whereas in two others bleeding was due to snaring of orbital tissues. In two of these three cases, intraoperative recognition and prompt treatment of the expanding hematoma resulted in preservation of vision. Motility disturbances due to extraocular muscle injury occurred in two patients after intranasal ethmoidectomy and in one patient after a Caldwell-Luc procedure. Bilateral blindness resulted from transection of both optic nerves in one patient during bilateral intranasal endoscopic ethmoidectomies. Recommendations for prevention, intraoperative recognition, and management of such ophthalmic complications of sinus surgery are given.