For a more extensive list of official Church documents, see this link.
For an excellent summary of the major social teachings provided by the Pontifical Council for Justice and Peace, see this link.
Quadragesimo Anno (After Forty Years) -- Pope Pius XI, 1931
Mater et Magistra (Christianity and Social Progress) -- Pope John XXIII, 1961
Applying the teachings of his predecessors to modern problems, and affirming the role of the Church as a teacher, and as a nurturing guardian of the poor and oppressed, John XXIII calls for a greater awareness of the need for all peoples to live as one community with a common good. Special attention is focused on the plight of the farmers and farm workers in depressed rural, agricultural economies.
Pacem in Terris (Peace on Earth) -- Pope John XXIII, 1963
Gaudium et Spes (Pastoral Constitution on the Church in the Modern World) Vatican Council II, 1965
Populorum Progressio (On the Development of Peoples) -- Pope Paul VI, 1967
Octogesima Adveniens (A Call to Action) -- Pope Paul VI, 1971
Justicia in Mundo (Justice in the World) -- Synod of Bishops, 1971
Laborem Exercens (On Human Work) -- Pope John Paul II, 1981
Solicitudo Rei Socialis (On Social Concern) -- Pope John Paul II, 1987
Centesimus Annus (The Hundredth Year) -- Pope John Paul II, 1991
Evangelium Vitae (The Gospel of Life) -- Pope John Paul II, 1995
Fides et Ratio (Faith and Reason) -- Pope John Paul II, 1998
Other Papal and Vatican Statements of Note
The Catechism of the Catholic Church, The Vatican, 1992
Catholic Social Teaching: The Catechism's Best Kept Secret
U. S. Bishops' Statements
Program of Social Reconstruction 1919
Pastoral Letter of 1919
Brothers and Sisters to Us 1979
Capital Punishment, 1980
Economic Justice All, 1986
Official Text
The Harvest of Justice is Sown in Peace, 1993
A Reflection of the National Conference of Catholic Bishops on the Tenth Anniversary of The Challenge of Peace
Communities of Salt and Light, 1993
A Decade after Economic Justice for All 1996
Sharing Catholic Social Teaching: Challenges and Directions, 1998
Everyday Christianity: To Hunger and Thirst for Justice, 2001