Abstract: Objectives : Continuous positive airway pressure (CPAP) is the 'gold standard' treatment for moderate-to-severe obstructive sleep apnea (OSA); adherence is an important issue. The aim of this paper is to review Belgian data on CPAP users and their adherence over a period of 11 years. Methods : Data delivered annually by the CPAP centers to the Belgian National Institute for Health Insurance (RIZIV/INAMI) were studied. Comments on these results were embedded in a narrative review. Results : On 1 January 2008 27.266 Belgian patients were treated with CPAP, at the end of 2018 this number increased to 121.605. In 2018, the short-term adherence (<= 3 months) to CPAP was at least twice as high compared to the United States: the CPAP termination rate in Belgium (mainly due to stop of reimbursement because adherence <4 h/night) was estimated to be 12.4%, considerably lower than the 31.1% of patients on CPAP in the United States using the device Conclusion : We speculate that this good adherence might be attributed to a stringent Belgian diagnostic and treatment convention model. This model uses 'gold standard' techniques (including in-hospital polysomnography), imposes a minimum capacity of medical doctors and paramedical collaborators, a strict follow-up of the patients, multidisciplinary care and proof of competency. Taking into account the increasing number of patients, a change in the Belgian care strategy is under consideration focusing on more out-of-centre patient's management; we propose a step-by step approach with careful monitoring of the impact of changing policy on adherence.