Refer to the Red Book." That's been the watchword for generations of healthcare professionals seeking trustworthy guidance on pediatric infectious disease prevention, management, and control. Now the 32nd edition continues this tradition of excellence with the latest clinical guidance on manifestations, etiology, epidemiology, diagnosis and treatment of more than 200 childhood infectious diseases. The 32nd edition provides evidence-based guidance on pediatric infections and vaccinations based on the recommendations of the committee as well as the combined expertise of the CDC, the FDA and hundreds of contributors. Red Book is an indispensable reference for pediatricians and pediatric infectious disease specialists and is useful for family medicine and emergency medicine physicians, as well. Public health and school health professionals, medical residents, and students also will find it a high-yield source of pediatric infectious disease and vaccine information. New in the 2021 Red Book: All chapters were assessed for relevance in the dynamic environment that is the practice of medicine today, and every chapter has been modified. Two chapters have been added to the 2021 edition: Pseudomonas aeruginosa Infections and a new "System-Based Treatment" table designed to aid in initial antibiotic selections by clinical conditions. Standardized approaches to disease prevention through immunizations, antimicrobial prophylaxis, and infection-control practices have been updated throughout the Red Book References to evidence-based policy recommendations have been updated throughout the Red Book. Appropriate chapters throughout the Red Book have been updated to be consistent with 2021 AAP and CDC vaccine recommendations for immunization of health care personnel, and drug recommendations from 2021 Nelson's Pediatric Antimicrobial Therapy.