Juan Guaidó, 35, is the leader of the opposition movement in Venezuela and the most potent threat to Nicolas Maduro's authoritarian government.
Guiadó, who helped found the Popular Will party in 2009, was elected to the National Assembly in 2015. He's become the face of the opposition movement in Venezuela despite his relative lack of inexperience.
Maduro has been working to undermine the National Assembly's authority for years, and his ruling Socialist party controls virtually every aspect of Venezuela's government. For his undemocratic efforts, Maduro has been decried by the international community.
Guiadó in early January was made the leader of the opposition-controlled parliament – the National Assembly. He is a junior member of the People's Will party but was made chairman of the legislature given the party's leaders are under house arrest, in exile, or in hiding.
Guaidó on January 23 declared himself the interim president of Venezuela in defiance of Maduro and amid nationwide protests. Speaking to thousands of cheering supporters, Guaidó said he was "formally assuming the responsibility of the national executive."
Venezuelans have been protesting against Maduro's government and the ruling Socialist party, which has pushed the country into economic collapse, for several years. Maduro's inept policies and dictatorial practices have led to hyperinflation and mass numbers of people to flee Venezuela. People, including children, have died of starvation.
Maduro had been sworn into a second six-year term in office just two weeks prior to Guaidó's stunning declaration, but his reelection in May 2018 was not recognized by the opposition amid allegations of vote buying and other undemocratic tactics. The US government also did not recognize Maduro's reelection.
Guaidó has pointed to a clause in the Venezuelan constitution that states the leader of the legislature becomes president when there is a "vacuum of power." He's asserted that the illegitimacy of Maduro's reelection has created such a situation, which is the basis of his claim to power.
The US government and a number of its allies have lined up to officially recognize Guaidó's claim to power.
"My duty is to call for free elections because there is an abuse of power and we live in a dictatorship," Guaidó told the BBC on January 29. "In Venezuela, we either accept domination, total oppression and torture ... from Maduro's regime, or we choose freedom, democracy and prosperity for our people." He said Maduro has been "killing young poor people" in Venezuela's streets.
A UN human rights spokesman on January 29 said more than 850 people were detained in Venezuela between January 21 and January 26, including 77 children, some as young as 12. Meanwhile, at least 40 were killed in recent violence in Venezuela, including 26 shot by pro-government forces.
Despite support from major powers like the US, Guaidó faces an uphill battle. He does not have the support of Venezuela's military, and Maduro's allies in the government have moved to freeze his assets and restrict his movements. Guaidó was arrested on January 13, but swiftly released.
Maduro also has the backing of Russia and China, which gives him leverage.
Ongoing protests could shift the tide in Guaidó's favor. The US has also hinted it's willing to use military force against Maduro if it comes to that.
Guaidó is confident there can be a peaceful transition of power in Venezuela. "We are sure we can achieve a peaceful transition – a transition and eventually free elections," he told CNN on January 29. "We must use great pressure for a dictator to leave, install a transitional government and have free elections."
In announcing himself interim president, Guaidó said, "It has to be the Venezuelan people, the armed forces, and the international community that allow us to assume power, which we will not let slip away." He has promised amnesty to the military if it withdraws support for Maduro.
Guaidó, an industrial engineer, was born in the port city of La Guaira in the state of Vargas. He's one of seven children.
After studying industrial engineering as an undergrad, Guaidó completed graduate degrees at George Washington University in Washington, DC, and Venezuelan private business school Instituto de Estudios Superiores de Administración.
He was reportedly driven into politics after a the government's ineffective response to a devastating, deadly flood in his community. As a student, he organized protests against Hugo Chavez, Maduro's late predecessor and the father of the socialist revolution in Venezuela.
Guaidó technically has no authority over Venezuela's government institutions but still wields a significant amount of influence moving forward. With that said, there are also fears that he's danger, especially after his arrest in mid-January. He's told supporters to continue peaceful protests in the event he's kidnapped.