Juan Gerardo Antonio Guaidó Márquez is a Venezuelan politician and opposition figure. He belonged to the social-democratic party Popular Will, and was a federal deputy to the National Assembly representing the state of Vargas. He was a key figure in the Venezuelan presidential crisis between 2019 and 2023, when he was recognized by 88 countries, the European Parliament, Andean Parliament, Organization of American States etc. as the legitimate president of Venezuela vis-à-vis Nicolás Maduro by 49 countries.
Guaidó's political career began when he emerged as a student leader in the 2007 Venezuelan protests. He then helped found the Popular Will party with Leopoldo López in 2009, and was elected to be an alternate deputy in the National Assembly one year later in 2010. In 2015, Guaidó was elected as a full-seat deputy. Following a protocol to annually rotate the position of President of the National Assembly among political parties, Popular Will nominated Guaidó for the position in 2019.