* Abbreviations: CPAP, : continuous positive airway pressure FRC, : functional residual capacity NIV, : noninvasive ventilation NRS, : noninvasive respiratory support Both the terms noninvasive respiratory support (NRS) and noninvasive ventilation (NIV) comprise different modes of supplying a gas admixture to the newborn infants without the need of endotracheal intubation. Hence, NRS refers to continuous positive airway pressure (CPAP) or intermittent positive airway pressure administered via face mask or nasal prongs. Although the use of nasal prongs is a somewhat invasive procedure, it is the general understanding that CPAP or intermittent positive pressure via nasal prongs is a noninvasive technique. In addition, although CPAP is not a mode of ventilation, the term NIV has been generally accepted and used as an equivalent for NRS. From here on, both terms noninvasive respiratory support and NIV will be used for the same purpose throughout this issue. Successful transition and adaptation to the extra-uterine environment implies successful accomplishment of a series of complex cardiopulmonary changes occurring in a very precise and synchronized sequence. In the first minutes after birth, fluid filling the lungs is cleared by the conjunction of mechanical forces imposed on the fetus during …