A supermajority, supra-majority, qualified majority or special majority, is a requirement for a proposal to gain a specified level of support which is greater than the threshold of more than one-half used for a majority. Supermajority rules in a democracy can help to prevent a majority from eroding fundamental rights of a minority. Changes to constitutions, especially those with entrenched clauses, commonly require supermajority support in a legislature. Parliamentary procedure requires that any action of a deliberative assembly that may alter the rights of a minority have a supermajority requirement, such as a two-thirds vote.