Extracorporeal membrane oxygenation (ECMO) is a technique for providing life support \nin severe but potentially reversible cardiorespiratory failure. The technique oxygenates \nblood outside the body, obviating the need for gas exchange in the lungs and, if \nnecessary, provides cardiovascular support. This enables the lungs to rest with use of \nminimal ventilator settings, thereby preventing injury from high oxygen concentration and \nbarotrauma. ECMO is most commonly used to support (nearly) mature newborn infants \nwith respiratory failure and pulmonary hypertension caused by meconium aspiration \nsyndrome (MAS), congenital diaphragmatic hernia (CDH), sepsis and idiopathic \npersistent pulmonary hypertension of the newborn (idiopathic-PPHN). This thesis \naddresses clinical studies evaluating several aspects of the acute phase of ECMO \ntreatment and long-term follow-up of newborns treated with ECMO for respiratory failure. \n\nChapter 1 is a general introduction to the developmental history of ECMO. It presents \nthe studied aspects of the acute phase (chapters 2 to 6) and long-term follow-up \n(chapters 7 to 9) together with the study aims.