The Nineteenth Amendment (Amendment XIX) to the United States Constitution prohibits the United States and its states from denying the right to vote to citizens of the United States on the basis of sex, in effect recognizing the right of women to vote.

The Nineteenth Amendment of the Constitution is an amendment of the Constitution of Ireland which permitted the state to be bound by the British–Irish Agreement (the bilateral portion of the Good Friday Agreement) and enabled the establishment of shared political institutions between Ireland and Northern Ireland.

The (Urdu: آئین پاکستان میں انیسویں ترمیم) a 2011 amendment reforming the judicial appointments procedure as well as expanding the Federally Administered Tribal Areas.