Ricardo Froilán Lagos Escobar (; March 2, 1938) is a lawyer, economist and social democrat politician, who served as president of Chile from 2000 to 2006. He won the 1999-2000 presidential election by a narrow margin in a runoff over Independent Democrat Union (UDI) candidate Joaquín Lavín. Lagos was the third president from the center-left Coalition of Parties for Democracy to have ruled Chile since 1990. He was succeeded on March 11, 2006 by Socialist Michelle Bachelet, from the same coalition. Since May 2007 he has served as a Special Envoy on Climate Change for the United Nations Secretary-General Ban Ki-moon.
He teaches political and economic development at Brown University in the United States.
He is also the former president of the Club of Madrid.