Among the myriad of diseases that can cause acute reversible neurological dysfunctions, the Posterior Reversible Encephalopathy Syndrome (PRES) with its diverse etiology and varied presentation needs attention. At risk population includes those with chronic hypertension, eclempsia, auto- immune disease, chronic kidney disease and drug induced especially anti-cancer and immunosuppressant drugs. Once thought of its relation only to existing hypertension, its always reversibility and affection only to posterior cerebral cortex, the term PRES is now a misnomer as this is not always reversible and is not necessarily restricted to posterior region of brain with advancement in radiological diagnostic techniques, the kidney diseases as risk factor for PRES is getting more and more popularity in a good subset of patients. However a prompt diagnosis and rapid correction of underline cause makes it reversible both clinically and radiologically.