Under the rules of the sponsoring organization (for example national federations such as American Contract Bridge League (ACBL) and the English Bridge Union (EBU), zonal organizations, and the World Bridge Federation (WBF)), certain conventions are alertable, the partner of the player making the conventional call must say "alert" (or show an alert card from the bidding box) before the right-hand opponent calls.
bridge | Ramsar Convention | Republican National Convention | Golden Gate Bridge | Brooklyn Bridge | Contract bridge | Sydney Harbour Bridge | National Convention | London Bridge | Fairport Convention | Democratic National Convention | Tower Bridge | European Convention on Human Rights | Eads Bridge | United Nations Framework Convention on Climate Change | Southern Baptist Convention | Forth Bridge | Auckland Harbour Bridge | Waterloo Bridge | Stamford Bridge | Convention on the Rights of the Child | Westminster Bridge | World Bridge Federation | The Bridge on the River Kwai | Pegasus Bridge | Manhattan Bridge | arch bridge | Tyne Bridge | Tappan Zee Bridge | Peace Bridge |