Chronic Suppurative Otitis Media (CSOM) is a chronic inflammation of the middle ear and mastoid cavity, which presents with a perforated tympanic membrane, through which microorganisms can enter into the middle ear. Infection can spread from the middle ear to vital structures such as the mastoid, facial nerve, labyrinth, lateral sinus, meninges, and brain. It is a common cause of hearing impairment and can occasionally lead to fatal intracranial infection.Prevalence surveys estimate that the global burden of illness from CSOM may involve 65 to 330 million individuals with draining ears. Looking into the magnitude of this global problem, which is still a burning issue, I was motivated to expand my research work in the form of a Book. This comprehensive overview of CSOM by a Clinical microbiologist with an extensive experience in the field of infectious diseases will be of immense help to Clinicians, Laboratory physicians, researchers, and students while conceptualizing the topic or dealing with CSOM patients.