Vitali Klitschko, Ukrainian boxer and politician, Mayor of Kiev
Vitali Volodymyrovych Klitschko (; Ukrainian: Віта́лій Володи́мирович Кличко́ [wiˈtɑl⁽ʲ⁾ij woloˈdɪmɪrowɪtʃ klɪtʃˈkɔ]; born 19 July 1971) is a Ukrainian politician and former professional boxer who serves as mayor of Kyiv and head of the Kyiv City State Administration, having held both offices since June 2014. Klitschko is a former leader of the Petro Poroshenko Bloc and a former Member of the Ukrainian Parliament. He became actively involved in Ukrainian politics in 2005 and combined this with his professional boxing career until his retirement from the sport in 2013. He holds a Doctoral Degree (Ph.D.) from Kyiv University's Physical Science Department.As a boxer, Klitschko won multiple world heavyweight championships. He held the World Boxing Organization (WBO) title from 1999 to 2000, the Ring magazine title from 2004 to 2005, and the World Boxing Council (WBC) title twice between 2004 and 2013. Overall, he defeated 15 opponents in world heavyweight title fights, and made 12 successful title defences. In 2011, Vitali and his younger brother Wladimir Klitschko entered the Guinness World Records as the pair of brothers with most world heavyweight title fight wins (30 at the time; 40 as of 2020). From 2006 until 2015, Vitali and Wladimir (also a multiple world champion) dominated heavyweight boxing, a period widely known as the "Klitschko Era" of the division. Klitschko's last fight was in 2012, but he remained the WBC heavyweight champion at age 42 when he announced his retirement in December 2013.

Klitschko formally began his political career in 2006 when he placed second in the Kyiv mayoral race. In 2010, he founded the party Ukrainian Democratic Alliance for Reform (UDAR) and was elected into parliament for this party in 2012. He was a leading figure in the 2013–2014 Euromaidan protests, and he announced his possible candidacy for the Ukrainian presidency but later withdrew and endorsed the eventual winner Petro Poroshenko. He was elected Mayor of Kyiv on 25 May 2014. He headed the election list of the winner of the 2014 Ukrainian parliamentary election, the Petro Poroshenko Bloc, but he gave up his parliamentary seat to stay on as Mayor of Kyiv. On 28 August 2015 the UDAR party merged into Petro Poroshenko Bloc. Klitschko thus became the new party leader. Klitschko was reelected as mayor on 15 November 2015. Klitschko revived UDAR, and left Petro Poroshenko Bloc with it, in May 2019 and simultaneously announced that UDAR would take part in the 2019 Ukrainian parliamentary election autonomously. UDAR however failed to win any seats.