“Sketch of a Projected Book about the Kingdom of God,” with Germain Grisez, in Moral Good, the Beatific Vision, and God’s Kingdom: Writings by Germain Grisez and Peter F. Ryan, S.J., ed. Peter J. Weigel (New York: Peter Lang, 2015), 149–65. ISBN 978-1-4331-2811-0

“Hell and Hope for Salvation,” with Germain Grisez, New Blackfriars 95 (2014): 606–15; available online at http://onlinelibrary.wiley.com/doi/10.1111/nbfr.12050/full

“Indissoluble Marriage: A Reply to Kenneth Himes and James Coriden,” with Germain Grisez, Theological Studies, 72:2 (2011): 369–415.

“The Significance of the Ultimate End for the Feeding of PVS Patients (a reply to Fr. Kevin O’Rourke, O.P.),” in Bioethics with Liberty and Justice: Themes in the Work of Joseph M. Boyle,ed. Christopher Tollefsen (New York: Springer, 2011), 75–93.

“Intellectual Formation for the Proclamation of the Kingdom,” Homiletic and Pastoral Review,111:5 (Feb. 2011): 74–75.

“AMDG: On the Significance for Sound Spiritual Formation of Seeking the Kingdom of God for the Glory of God,” in Seminary Theology II: Theology and Spiritual Direction in Dialogue, ed. James Keating (Omaha, Neb.: Institute for Priestly Formation, 2011), 123–46.

“New Problems concerning Procreation: Symposium on Dignitas Personae, ” National Catholic Bioethics Quarterly, 9:3 (Sept. 2009): 467–70.

“Reply to Fr. John McDermott, S.J.,” Fellowship of Catholic Scholars Quarterly, 31:2 (Summer 2008): 33–34; and 31:3 (Fall 2008): 42–43.

“What Is Our Moral Obligation to the Abandoned Embryo?” (Presidential Address), Proceedings of the Jesuit Philosophical Association, 62 (2008): 7–18.

“Taking Our Bodies Seriously: Holy Communion in the Eucharist and Marriage,” Fellowship of Catholic Scholars Quarterly, 30:2 (Summer 2007): 4–10.

“How to Discern the Elements of Your Personal Vocation,” Fellowship of Catholic Scholars Quarterly, 30:2 (Summer 2007): 11–18; also available at http://www.twotlj.org/PeterRyanDiscernment.pdf

“Our Moral Obligation to the Abandoned Embryo,” in Human Embryo Adoption: Biotechnology, Marriage, and the Right to Life, ed. Rev. Thomas V. Berg, L.C., and Edward J. Furton (Philadelphia: National Catholic Bioethics Center, 2006), 297–325.

“Secularist and Christian Views of Human Nature and Its Fulfillment: Implications for Bioethics and Environmentalism,” in Human Nature in Its Wholeness, ed. Daniel N. Robinson, Gladys M. Sweeney, and Richard Gill, L.C. (Washington, D.C.: Catholic University of America Press, 2006), 57–79.

“The Desire for Fulfillment: Comments on an Issue Raised in the Letter to Families,” in Creed and Culture: Jesuit Studies of Pope John Paul II, ed. Joseph W. Koterski, S.J., and John J. Conley, S.J. (Philadelphia: St. Joseph’s University, 2004), 215–22.

“Second Response” to Cardinal Francis George, “Self-Gift in Generative Love,” in Spiritual Fatherhood: Living Christ’s Own Revelation: Third Annual Symposium on the Spirituality and Identity of the Diocesan Priest, ed. Edward G. Matthews, Jr. (Omaha, Neb.: Institute for Priestly Formation, 2003), 29–31.

“How Can the Beatific Vision both Fulfill Human Nature and Be Utterly Gratuitous?” Gregorianum, 83:4 (2002), 717–54; reprinted in Moral Good, the Beatific Vision, and God’s Kingdom: Writings by Germain Grisez and Peter F. Ryan, S.J., 49–83.

“A Single Ultimate End Only for ‘Fully Rational’ Agents? A Critique of Scott MacDonald’s Interpretation of Aquinas,” American Catholic Philosophical Quarterly, 75 (2001): 433–38.

“Must the Acting Person Have a Single Ultimate End?” Gregorianum, 82:2 (2001): 325–56; reprinted in Moral Good, the Beatific Vision, and God’s Kingdom: Writings by Germain Grisez and Peter F. Ryan, S.J., 17–47.

“Fulfillment as Human in the Beatific Vision? Problems of Fittingness and Gratuity,” American Journal of Jurisprudence, 46 (2001): 153–63.

Archdiocesan Moral Theology Course Outlines: A Teacher’s Guidebook for a Course in Moral Theology (Baltimore: Archdiocese of Baltimore Church Leadership Institute, 2001).

“The Value of Life and Its Bearing on Three Issues of Medical Ethics,” in Life and Learning: Proceedings of the Ninth University Faculty for Life Conference, 9 (Washington, D.C.: University Faculty for Life, 2000), 41–57; a differently formatted version: http://www.uffl.org/vol%209/ryan9.pdf.

“Gateway to a Uniquely Georgetown Education: A Fresh Introduction to Ex Corde Ecclesiae,” Fellowship of Catholic Scholars Quarterly, 22:2 (Spring 1999): 15–19, reprinted from The Georgetown Academy (Winter 1999) and reprinted with Ex Corde Ecclesiae by the Cardinal Newman Society.

 “God the Father as Center of Family Life” in God: The Father of Jesus and Humanity: Preparing to Celebrate the Great Jubilee Year 2000 (Benin City, Nigeria: Archdiocese of Benin City, 1999), 46–56.

 “The Catholic University and the Idea of Academic Freedom,” in The Nature of Catholic Higher Education: Proceedings of the Eighteenth Convention of the Fellowship of Catholic Scholars,ed. Anthony J. Mastoeni (Steubenville, Ohio: Franciscan University, 1996), 133–56; video of a slightly amended version: http://www.faithandreason.com/fr-peter-ryan-sj-catholic-university-idea-academic-freedom/