Introduction This thesis consists of studies that relate to outcomes of preterm infants after using automated oxygen control (AOC). Supplemental oxygen is an important tool in battling hypoxia related to prematurity but can be harmful. Hyperoxia resulting from inappropriate oxygen administration can lead to morbidities such as bronchopulmonary dysplasia, retinopathy of prematurity and neurodevelopmental impairment. Therefore, supplemental oxygen must be carefully titrated within a therapeutic range. An automated oxygen controller has been proven to be more successful than manual control in titrating oxygen within this range. In this thesis, a review is given of which algorithms are available, and how they work. Thereafter, we report on the effectivity of two automated oxygen controllers used in the NICU, followed by clinical and long-term outcomes after using AOC. We conclude with a general discussion of this thesis.