The Orange Revolution engulfed Ukraine following the November 2004 presidential run-off election between Viktor Yushchenko, which was marred by massive voting irregularities. Hundreds of thousands of Ukrainians took to the streets of Kyiv and other cities in protest. The crisis ended on December 8 with an agreement to repeat the run-off election, a revised presidential election law that made vote falsification less likely, and constitutional amendments that gave Ukraine a parliamentary-presidential model of government.