This section of Current Opinion in Pediatrics focuses on issues in infectious disease that are commonly encountered in pediatric office practice. Dr. Paul McCarthy discusses recent literature regarding the evaluation and management of acute fevers without apparent source on clinical examination in infants and children, and the evaluation of children with prolonged fevers of unknown origin. Dr. David Bachman reviews recent literature about lower respiratory tract infection in children and focuses on community acquired pneumonias, aspiration pneumonia, pneumonia in children with malignancy, and the diagnosis and management of respiratory syncytial virus infections. Dr. Eugene Shapiro discusses literature concerning several infectious diseases commonly seen in office settings and concerning which recent developments are of interest: Lyme disease, cat-scratch disease, illness caused by Haemophilus influenzae type b, chlamydia infections, Mycobacterium tuberculosis infections, streptococcal pharyngitis, otitis media, and pertussis. Dr. Michael Baron reviews recent literature about gastroenteritis and diarrhea of infancy and early childhood and discusses diagnostic, preventive, and therapeutic advances as well as recent reviews about the topic that he has found to be of high quality.