Eye motility is controlled by third nerve (occulomotor nerve). Third nerve palsy can effect eye motility, pupillary function or both simultaneously. It may present as diplopia, ptosis or difficulty to adduct eye. The eye stays out and down when the patient looks straight ahead. The effected pupil stays dilated and has impaired light reflex. It can usually occur in aneurysms, brain herniation, meningitis, diabetes and hypertension. It is assessed by clinical examination and scans like CT scan and MRI. Treatment is cause related.