Remixes will inevitably encounter legal problems when the whole or a substantial part of the original material has been reproduced, copied, communicated, adapted or performed – unless a permission has been given in advance through a voluntary open content license like a Creative Commons license, there is fair dealing involved (the scope of which is extraordinarily narrow), a statutory license exists, or permission has been sought and obtained from the copyright owner. Generally, the courts consider what will amount to a substantial part by reference to its quality, as opposed to quantity and the importance the part taken bears in relation to the work as whole.