John Paul II dedicates this encyclical to the twentieth anniversary of Paul VI’s Populorum Progressio, rereading its teaching on the development of peoples amid the altered conditions of the late 1980s. He presents Catholic social doctrine as continuous in its Gospel-based principles yet renewed in their application, and treats development as a global, moral question rather than a merely economic one. Widening inequality between North and South, poverty, unemployment, international debt, unjust financial systems, ideological blocs, the arms race, refugees, terrorism, and coercive population policies expose failures in contemporary models of progress. Authentic development embraces the whole person: material, cultural, political, moral, and spiritual. It respects human rights, the universal destination of goods, personal initiative, national responsibility, environmental stewardship, and the transcendent vocation of humanity. The encyclical identifies the desire for profit and thirst for power as “structures of sin,” overcome through conversion and solidarity. It calls for a preferential option for the poor, reform of international trade and financial institutions, regional cooperation among developing nations, and peaceful commitment by individuals, families, and states. The Eucharist gives Christians strength for this mission, while human efforts toward justice anticipate the Kingdom without being identical with it.