The motivation for this book comes from the fact that Infectious Diseases has not yet developed as a specialty in the Indian subcontinent, even though India has more medical graduates trained in Clinical Microbiology than any other country. Treatment of infectious diseases by physicians trained in the subject has been shown to significantly improve patient outcomes in the USA. This book is a compilation of 65 cases of severe infectious diseases, all of which, in addition to being treatable, are actually curable. This is not merely a collection of case reports but a case-based learning tool aimed at providing help in rationalizing differential diagnoses based on presentation and relevant physical findings. The most relevant investigations lead to a presumptive diagnosis on which presumptive therapy can be based. Once the patient survives the first 24-28 hours, further diagnostic work-up helps to confirm the diagnosis and provide definitive therapy for an appropriate duration. This is perhaps the first time a book on clinical management of severe infections based on the most likely pathogens and presumptive use of appropriate antibiotics is being made available to students, trainees and practising physicians and surgeons in the Indian subcontinent.