When can a court be classified as a supreme court? This question is rarely asked in discussions about supreme courts, which is surprising. Very often it is assumed that courts high up in the judicial hierarchy that produce influential case law can be classified as such, but obviously more is needed if one uses the notion ‘supreme’. This introduction discusses some of the additional requirements that need to be met in order to classify a court as ‘supreme’ as well as the access filters that have been introduced in various jurisdictions in order to allow supreme courts to concentrate on their main tasks. The starting point of the discussion is the Chinese Supreme People's Court in relation to a selection of Western supreme courts.