The property of being toxic to the ear, especially, to the auditory nerve or cochlea and the vestibular system, is termed as ototoxicity. The effects of toxicity can be permanent and irreversible or temporary and reversible. There are many drugs used in clinical situations that are ototoxic and are prescribed for very serious health conditions despite the risk of hearing disorders. A few of these drugs are antibiotics such as tobramycin, streptomycin, gentamicin, platinum-based chemotherapy agents such as carboplatin and cisplatin and loop diuretics such as furosemide. Several nonsteroidal anti-inflammatory drugs have also been found to be ototoxic. This may result in dysequilibrium, sensorineural hearing loss, or both. This book traces the progress of this field and highlights some of its key concepts. It will also provide interesting topics for research which interested readers can take up. This book will prove to be immensely beneficial to students and researchers in this field.