She received her Ph.D. from the American Studies Program at Harvard University. Her research and teaching examine social movements in the Americas, with a special focus on the contributions of women and people of African and Caribbean descent. Her book manuscript, A Global Vision: Dr. Ana Livia Cordero and the Puerto Rican Liberation Struggle, emphasizes the influential role of Puerto Rico and Puerto Ricans in Cold War-era freedom struggles by centering the life of Ana Livia Cordero, a physician who forged connections between anti-imperialist movements across the Third World. Placido worked to preserve Cordero's archival collection at Harvard's Schlesinger Library, and she has received support for her research from the Ford and Mellon Foundations.