Works

Against Jovinianus
In two books, each in its own file, with notes. The first book is entirely taken up with Jovinian's assertion that virginity is no better than marriage. The latter book examines Jovinian's propositions about abstinence, degrees of sin, the sinlessness of believers, and degrees of punishment or reward in the afterlife.
http://www.ccel.org/ccel/schaff/npnf206.vi.vi.html

Against the Pelagians
Dialogue Between Atticus, a Catholic, and Critobulus, a Heretic. In three books, with introduction, notes, and author's prologue.
http://www.ccel.org/ccel/schaff/npnf206.vi.ix.html

Against Vigilantius
Jerome turns on his former friend, who had objected to reverencing relics, vigils, the practice of sending alms to Jerusalem, and an exaggerated (in the opinion of Vigilantius) esteem for virginity.
http://www.ccel.org/ccel/schaff/npnf206.vi.vii.html

Apology for Himself Against the Books of Rufinus
W.H. Fremantle translation, from the Nicene and Post-Nicene Fathers of the Christian Church, second series, vol. 3. Presented as three books, with notes and links to contents, previous, and next.
http://www.ccel.org/ccel/schaff/npnf203.vi.xii.html

The Dialogue Against the Luciferians
A literary dialogue between "Orthodoxus" and "Helladius the Luciferian". The introduction from A Select Library of Nicene and Post-Nicene Fathers of the Christian Church, second series, vol. 6, sets the stage. Lucifer, a bishop, and his party, against the decision of a council of the Church and against SS. Jerome and Athanasius, wished to show no mercy to penitents who had fallen into Arianism.
http://www.ccel.org/ccel/schaff/npnf206.vi.iv.html

The Life of Hilarion
In HTML, with notes, at Christian Classics Ethereal Library.
http://www.ccel.org/ccel/schaff/npnf206.vi.ii.html

The Life of Malchus, the Captive Monk
In HTML, with notes, at Christian Classics Ethereal Library.
http://www.ccel.org/ccel/schaff/npnf206.vi.iii.html

The Life of Paulus the First Hermit
St. Jerome's first published work. From the Nicene and Post-Nicene Fathers of the Christian Church, second series, vol. 6.
http://www.ccel.org/ccel/schaff/npnf206.vi.i.html

Lives of Illustrious Men
And he does mean men. Ernest Cushing Richardson translation. With notes and introduction ("previous"). From the Nicene and Post-Nicene Fathers of the Christian Church, second series, vol. 3.
http://www.ccel.org/ccel/schaff/npnf203.v.html

The Perpetual Virginity of the Virgin Mary: Against Helvidius
A certain Helvidius said that since Jesus had brothers, Mary was not a virgin after his birth. He also maintained that this demonstrates that marriage is better than virginity. Jerome takes the opposite view.
http://www.ccel.org/ccel/schaff/npnf206.vi.v.html

To Pammachius Against John of Jerusalem
Unpublished during Jerome's lifetime. An ugly little chapter in Church history. Epiphanius of Salamis, a heresy-hunting bishop, had castigated Jerome's bishop John of Jerusalem for Origenism. Epiphanius then urged Jerome to repudiate John, ordained Jerome's brother by force, and Jerome was effectively excommunicated for approximately four years.
http://www.ccel.org/ccel/schaff/npnf206.vi.viii.html