Purpose: To emphasize that papilledema and other ophthalmic manifestations may occur in the syndrome of headache, neurologic deficits, and cerebrospinal fluid lymphocytosis (HaNDL). Design: Two interventional case reports. Methods: Two patients were seen with ophthalmologic findings, including decreased vision, papilledema, sixth nerve palsy, and a variety of neurologic deficits. Each underwent cerebrospinal fluid analysis and intracranial pressure measurement by spinal tap and neuroimaging studies to confirm the diagnosis of HaNDL. Results: Both patients received acetazolamide to lower intracranial pressure. The first patient had complete resolution of signs and symptoms. The second, who was also given systemic corticosteroids, was left with diminished visual acuity in the right eye with nasal visual field loss and optic atrophy. Conclusions: The diagnosis of HaNDL is one of exclusion, which must be made in conjunction with a neurologist. HaNDL may be accompanied by elevated intracranial pressure and papilledema. As in other disorders causing papilledema, these patients may have permanent visual sequelae. Recognition by the ophthalmologist of this rarely reported syndrome will facilitate prompt patient diagnosis and treatment. © 2003 by the American Academy of Ophthalmology.