diff --git a/src/data/hours/lauds-psalmody-overrides/decollation-of-st-john-baptist.yml b/src/data/hours/lauds-psalmody-overrides/decollation-of-st-john-baptist.yml
new file mode 100644
index 0000000..af83142
--- /dev/null
+++ b/src/data/hours/lauds-psalmody-overrides/decollation-of-st-john-baptist.yml
@@ -0,0 +1,27 @@
+# Verified against Divinum Officium (Tridentine 1906/1910 and Divino
+# Afflatu 1954, `[Ant Vespera]`), Latin/Sancti/08-29.txt +
+# English/Sancti/08-29.txt, 2026-08-29 — Lauds reuses the Vespers set
+# verbatim (`[Ant Laudes]` -> `@:Ant Vespera`).
+id: decollation-of-st-john-baptist
+groups:
+  - psalms: [92]
+    antiphon:
+      la: "Heródes enim ténuit * et ligávit Joánnem et pósuit in cárcerem propter Herodíadem."
+      en: "For Herod had laid hold upon John, * and bound him, and put him in prison, for Herodias' sake."
+  - psalms: [99]
+    antiphon:
+      la: "Dómine mi rex, * da mihi in disco caput Joánnis Baptístæ."
+      en: "O Lord my King, * give me in a charger the head of John the Baptist."
+  - psalms: [62]
+    antiphon:
+      la: "Puéllæ saltánti * imperávit mater: Nihil áliud petas, nisi caput Joánnis."
+      en: "The damsel danced, * and her mother charged her, saying: See thou ask nothing, but only the head of John."
+canticle:
+  id: canticum-trium-puerorum
+  antiphon:
+    la: "Arguébat * Heródem Joánnes propter Herodíadem, quam túlerat fratri suo Philíppo uxórem."
+    en: "John had rebuked Herod for Herodias' sake, * his brother Philip's wife, for he had taken her."
+laudate:
+  antiphon:
+    la: "Da mihi in disco * caput Joánnis Baptístæ. Et contristátus est rex propter jusjurándum."
+    en: "Give me in a charger the head of John the Baptist. * And the King was sorry, for his oath's sake."
diff --git a/src/data/hours/vespers-psalmody-overrides/saints/decollation-of-st-john-baptist.yml b/src/data/hours/vespers-psalmody-overrides/saints/decollation-of-st-john-baptist.yml
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+++ b/src/data/hours/vespers-psalmody-overrides/saints/decollation-of-st-john-baptist.yml
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+# Verified against Divinum Officium (Tridentine 1906/1910 and Divino
+# Afflatu 1954, `[Ant Vespera]`), Latin/Sancti/08-29.txt +
+# English/Sancti/08-29.txt, 2026-08-29. The reference's own `[Rule]`
+# ("Psalm5 Vespera=116") is a secular five-psalm-Vespers detail that
+# doesn't apply to vu's Monastic-1617-structured (four-psalm) Vespers —
+# same 109/111/112/115 baseline as common-of-a-martyr.yml's own Vespers
+# psalmody, with this feast's own first four proper antiphons (of its
+# five, `[Ant Vespera]` 1-4) substituted in; the fifth ("Da mihi in
+# disco...") has no corresponding slot here and is used only at Lauds'
+# Laudate psalm instead (see lauds-psalmody-overrides/decollation-of-st-
+# john-baptist.yml).
+id: decollation-of-st-john-baptist
+groups:
+  - psalms: [109]
+    antiphon:
+      la: "Heródes enim ténuit * et ligávit Joánnem et pósuit in cárcerem propter Herodíadem."
+      en: "For Herod had laid hold upon John, * and bound him, and put him in prison, for Herodias' sake."
+  - psalms: [111]
+    antiphon:
+      la: "Dómine mi rex, * da mihi in disco caput Joánnis Baptístæ."
+      en: "O Lord my King, * give me in a charger the head of John the Baptist."
+  - psalms: [112]
+    antiphon:
+      la: "Puéllæ saltánti * imperávit mater: Nihil áliud petas, nisi caput Joánnis."
+      en: "The damsel danced, * and her mother charged her, saying: See thou ask nothing, but only the head of John."
+  - psalms: [115]
+    antiphon:
+      la: "Arguébat * Heródem Joánnes propter Herodíadem, quam túlerat fratri suo Philíppo uxórem."
+      en: "John had rebuked Herod for Herodias' sake, * his brother Philip's wife, for he had taken her."