Oral Rehydration Solution (ORS) is one of the simplest yet most effective ways to prevent and treat dehydration caused by diarrhoea and vomiting. It works by replacing the water and essential electrolytes such as sodium and potassium that the body loses during illness. Although ORS is highly effective for mild to moderate dehydration, it is not a substitute for medical care when warning signs develop. When prepared correctly and used promptly, ORS remains one of the most effective, affordable, and lifesaving treatments for dehydration. Understanding the correct method of preparation and avoiding common mistakes can significantly improve recovery and reduce the risk of complications.