Survival of extremely preterm neonates has continuously improved over the past five decades. The reason for this is the tremendous progress in the fields of perinatology and neonatology, as well as the understanding of the issues related to extremely preterm birth. Although the neurodevelopmental outcome of these extremely vulnerable preterm infants has also significantly improved, the pace of its improvement appears to have lagged behind that of survival. Extremely premature infants make up a very small proportion of the total premature births, but despite that contribute the most to both neonatal and infant morbidity and mortality. One of the main challenges faced by perinatal and neonatal medicine is to define the level of fetal maturity below which survival and/or acceptable neurodevelopmental outcomes are highly unlikely. This refers to the period of periviability, as well as the threshold of viability, which is the agreed-upon gestational age at which half of the newborns survive and half do not. It is necessary to understand and explore these terms in order to make proper and justified decisions regarding the management of extremely preterm infants. Furthermore, there is a significant need for the development of uniform guidelines and new clinical concepts for this population. When developing guidelines, it is important to respect ethical principles and analyze the main outcomes of extreme prematurity and the key factors that influence them. In the developed world, there are numerous national guidelines and guidelines from healthcare societies available, which, based on different sources of data, may vary to a greater or lesser extent. Therefore, it is necessary to continue researching and comparing findings with the main goal of providing the best possible care and support for extremely preterm infants and their families.