María de Lourdes Santiago Negrón is a Puerto Rican lawyer and politician from Adjuntas. She is the current vice-president of the Puerto Rican Independence Party (PIP) and in 2004 became the first woman from that party to be elected into the Senate in the history of Puerto Rico. She currently serves as Senator at-large at the Puerto Rico Senate after being elected in 2020 with the most votes of any candidate.
Santiago Negrón was born in Adjuntas on November 13, 1968, to Ernesto Santiago and Haydée Negrón. After graduating from high school in Adjuntas in 1986, she earned a bachelor's degree in theatre and a Juris Doctor from the University of Puerto Rico at Rio Piedras.
From 1997 to 2000, she worked as a legal counsel for Victor García San Inocencio while he served in the House of Representatives of Puerto Rico, and for Manuel Rodríguez Orellana and Fernando Martín García while they served as Senators.