Robin Sequence (RS) is characterized by micrognathia and upper airway obstruction (UAO) caused by glossoptosis resulting in respiratory and feeding problems of varying severity. According to the original RS definition a cleft palate is associated with RS, but not part of the definition. Reported incidence numbers range from approximately 1:8,000 to 1:14,000 births. RS is very heterogenic, can occur in an isolated form, but is often accompanied by a syndrome. Pathogenesis of RS remains unclear. Management options are: Prone/lateral positioning, nasopharyngeal airway (NPA); tongue-lip adhesion (TLA); mandibular distraction (MDO); and tracheotomy. Controversy exists in literature regarding RS definition, prevalence, pathogenesis and best management. The studies presented in the first part of this thesis focus on providing information on currently used RS definitions and management schedules, RS prevalence and underlying pathogenesis. In the second part we look for objective criteria for RS diagnosis, while the third part gives insight in quality of life in RS patients and their parents.