In his "A History of Economic Ideas," Robert Lekachman has a short section called "Papal Economics." The following are some of the main writings that touch on this subject. Leo XIII, Encyclical Letter Rerum Novarum (1891) On Capital And Labor http://www.vatican.va/holy_father/leo_xiii/encyclicals/documents/hf_l- xiii_enc_15051891_rerum-novarum_en.html Leo XIII, Encyclical Letter Libertas (1888) On The Nature Of Human Liberty http://www.vatican.va/holy_father/leo_xiii/encyclicals/documents/hf_l- xiii_enc_20061888_libertas_en.html Pius XI, Encyclical Letter Quadragesimo Anno (1931) On Reconstruction Of The Social Order http://www.vatican.va/holy_father/pius_xi/encyclicals/documents/hf_p- xi_enc_19310515_quadragesimo-anno_en.html John XXIII, Encyclical Letter Mater et Magistra (1961) On Christianity And Social Progress http://www.vatican.va/holy_father/john_xxiii/encyclicals/documents/hf_j- xxiii_enc_15051961_mater_en.html Paul VI, Encyclical Letter Populorum Progressio (1967) On The Development Of Peoples http://www.vatican.va/holy_father/paul_vi/encyclicals/documents/hf_p- vi_enc_26031967_populorum_en.html John Paul II, Encyclical Letter Laborem Exercens (1981) On Human Work http://www.vatican.va/edocs/ENG0217/_INDEX.HTM John Paul II, Encyclical Letter Sollicitudo Rei Socialis (1987) on the twentieth anniversary of "Populorum Progressio" http://www.vatican.va/edocs/ENG0223/_INDEX.HTM John Paul II, Encyclical Letter Centesimus Annus (1991) On the hundredth anniversary of Rerum Novarum http://www.vatican.va/edocs/ENG0214/_INDEX.HTM Michael Nuwer