Sepsis is a significant cause of morbidity and mortality for neonates and infants. Neonates are at increased risk for sepsis due to their immature immune system. Bacterial, viral, and fungal organisms may cause sepsis in the young patient. Identifying septic neonates upon presentation to their primary care physician or the emergency department remains a challenge given the nonspecific manifestations of illness. Suspicion for sepsis should prompt evaluation to identify a source to tailor treatment appropriately. Timely diagnosis and management of neonatal sepsis, especially for those in septic shock, will lead to improved outcomes. The following article presents an overview of the most common organisms causing disease, clinical presentation, evaluation, and management for the neonate or infant presenting with suspected sepsis.