In this issue of Clinics in Perinatology, guest editors Drs. Sagori Mukhopadhyay and Karen M. Puopolo bring their considerable expertise to the topic of Perinatal and Neonatal Infections. Top experts review the fundamentals of neonatal infections and discuss the changing landscape of infectious disease and its management. Articles cover disease epidemiology, infection-related issues that have come into focus as neonatal practice evolves, the use of genomics to gain understanding of late-onset sepsis pathogenesis, consideration of circadian biology in infection transmission and acquisition, and more.