Fever is one of the most common presenting complaints in Pediatric practice. It can be a cause of concern to parents and the treating Pediatrician. This book describes a practical, case-based approach to diagnosing the cause of fever. The presentation simulates everyday challenges in the outpatient clinic and in-patient ward rounds, taking the learner systematically through the process of targeted history and focused clinical examination, which should result in making a provisional clinical diagnosis. A discussion on possible differentials, rational use of investigations, interpretation of lab reports, and treatment follows this. One of the unique features of this book is the initial note on parental counseling in challenging situations. The chapters provide a system-wise syndromic approach to diagnosing infections through case vignettes. It also includes cases with multisystem involvement and explanations of when to suspect non-infectious causes. This book will be of immense use to Pediatric postgraduate trainees and practicing Pediatricians. It covers pitfalls in diagnosis, atypical presentations, complications of common illnesses, causes of failure to respond to treatment, and common fallacies in interpreting lab results. The recent advances and the use of diagnostic facilities are explained.