Frequent and loud snoring is a very frequent condition in prepubertal children affecting approximately 10% of all 2-8 year old children. If polysomnographical evaluations are performed in these snoring children, approximately 10% will be diagnosed with obstructive sleep apnoea (OSA). The pathophysiology of OSA in children is still poorly understood. Indeed, while adenotonsillar hypertrophy is certainly a major contributor to OSA, other factors need to be implicated for OSA to develop. In recent years, it has become apparent that OSA and snoring are not as innocuous as previously thought. Indeed, epidemiological and pre-post treatment analyses have identified substantial morbidities that primarily affect cardiovascular and neurobehavioural systems, namely pulmonary hypertension, systemic elevation of arterial blood pressure, nocturnal enuresis, reduced somatic growth, behavioural problems that resemble attention deficit-hyperactivity disorder, as well as learning and cognitive deficits. These problems are associated with marked increases in healthcare-related costs. More importantly, if timely diagnosis and intervention are not implemented, some of these morbid complications may not be completely reversible, leading to long-lasting residual consequences.