Against the background of ecological devastation in the Americas, a growing list has emerged of environmental defenders whose care for our common home has cost them their lives. In Ecomartyrdom in the Americas, Elizabeth Gandolfo explores the meaning of their witness in relation to three recent developments in Catholic theology: the expanded understanding of martyrdom to include those who die in defense of gospel values (justice, concern for the poor); the expansion of Catholic social teaching to include care for creation; and the call for interreligious dialogue and cooperation.