diff --git a/crates/engine/src/cmd/shape/appearance.rs b/crates/engine/src/cmd/shape/appearance.rs
index 460565f7..09a0e236 100644
--- a/crates/engine/src/cmd/shape/appearance.rs
+++ b/crates/engine/src/cmd/shape/appearance.rs
@@ -108,7 +108,7 @@ pub(crate) fn gradient_param(v: &Value) -> Option<Gradient> {
             scaled: false,
         },
     };
-    Some(Gradient { tile: [0.0; 4], stops, shape, rotate_with_shape: v.get("rotateWithShape").and_then(Value::as_bool).unwrap_or(true) })
+    Some(Gradient { tile: [0.0; 4], stops, shape, rotate_with_shape: v.get("rotateWithShape").and_then(Value::as_bool).unwrap_or(true), flip: None })
 }
 
 /// Fill and outline apply to a group's visible members as well as its container. Other edits
diff --git a/crates/engine/src/cmd/smartart/paint.rs b/crates/engine/src/cmd/smartart/paint.rs
index fc75a1f9..e49efd90 100644
--- a/crates/engine/src/cmd/smartart/paint.rs
+++ b/crates/engine/src/cmd/smartart/paint.rs
@@ -99,6 +99,8 @@ pub(super) fn paint(d: &Diagram, sh: &mut Shape, i: usize, light: bool) {
                 shape: GradientShape::Linear { angle: 90.0, scaled: false },
                 rotate_with_shape: true,
                 tile: [0.0; 4],
+
+                flip: None,
             }));
             sh.line = Some(Line::solid(ColorRef::scheme(SchemeSlot::Lt1), 1.0));
             sh.effects = Some(Effects { outer_shadow: Some(shadow(8.0, 5.0)), ..Default::default() });
diff --git a/crates/model/src/style.rs b/crates/model/src/style.rs
index 83c494bd..a653da93 100644
--- a/crates/model/src/style.rs
+++ b/crates/model/src/style.rs
@@ -72,6 +72,36 @@ pub struct GradientStop {
     pub color: ColorRef,
 }
 
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum GradientFlip {
+    None,
+    X,
+    Y,
+    Xy,
+}
+
+impl GradientFlip {
+    pub fn xml(self) -> &'static str {
+        match self {
+            GradientFlip::None => "none",
+            GradientFlip::X => "x",
+            GradientFlip::Y => "y",
+            GradientFlip::Xy => "xy",
+        }
+    }
+
+    pub fn from_xml(value: &str) -> Option<Self> {
+        match value {
+            "none" => Some(GradientFlip::None),
+            "x" => Some(GradientFlip::X),
+            "y" => Some(GradientFlip::Y),
+            "xy" => Some(GradientFlip::Xy),
+            _ => None,
+        }
+    }
+}
+
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase", tag = "kind")]
 pub enum GradientShape {
@@ -90,6 +120,8 @@ pub enum GradientShape {
 pub struct Gradient {
     pub stops: Vec<GradientStop>,
     pub shape: GradientShape,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub flip: Option<GradientFlip>,
     #[serde(default = "crate::yes")]
     pub rotate_with_shape: bool,
     /// `a:tileRect`: the box the gradient is laid out in, as insets from the shape's box
diff --git a/crates/model/src/tests.rs b/crates/model/src/tests.rs
index 38d815ef..1fd29aef 100644
--- a/crates/model/src/tests.rs
+++ b/crates/model/src/tests.rs
@@ -73,8 +73,13 @@ fn a_gradient_without_stops_takes_them_from_its_style() {
     let p = Presentation::default();
     let s = &p.slides[0];
     let ctx = Ctx::for_slide(&p, s).unwrap();
-    let own =
-        style::Gradient { tile: [0.0; 4], stops: vec![], shape: style::GradientShape::Linear { angle: 45.0, scaled: true }, rotate_with_shape: true };
+    let own = style::Gradient {
+        tile: [0.0; 4],
+        stops: vec![],
+        shape: style::GradientShape::Linear { angle: 45.0, scaled: true },
+        rotate_with_shape: true,
+        flip: None,
+    };
     let mut st = ShapeStyle::accent(SchemeSlot::Accent2);
     st.fill_ref.0 = 3;
     let sh = Shape { style: Some(st.clone()), fill: Some(Fill::Gradient(own.clone())), ..Default::default() };
diff --git a/crates/model/src/theme.rs b/crates/model/src/theme.rs
index 870a8bb5..27fe93e3 100644
--- a/crates/model/src/theme.rs
+++ b/crates/model/src/theme.rs
@@ -115,6 +115,8 @@ pub fn default_format() -> FormatScheme {
             ],
             shape: GradientShape::Linear { angle: 90.0, scaled: false },
             rotate_with_shape: true,
+
+            flip: None,
         })
     };
     FormatScheme {
diff --git a/crates/pptx/src/read/dml.rs b/crates/pptx/src/read/dml.rs
index 767b7dc0..626f5877 100644
--- a/crates/pptx/src/read/dml.rs
+++ b/crates/pptx/src/read/dml.rs
@@ -3,8 +3,8 @@
 use deckcraft_color::{ColorTransform, Rgba, SchemeSlot};
 use deckcraft_geom::{Xfrm, emu_to_pt};
 use deckcraft_model::style::{
-    ColorBase, ColorRef, Compound, Dash, Effects, Fill, Glow, Gradient, GradientShape, GradientStop, Line, LineCap, LineEnd, LineJoin, PatternFill,
-    PictureFill, PictureMode, Reflection, Shadow,
+    ColorBase, ColorRef, Compound, Dash, Effects, Fill, Glow, Gradient, GradientFlip, GradientShape, GradientStop, Line, LineCap, LineEnd, LineJoin,
+    PatternFill, PictureFill, PictureMode, Reflection, Shadow,
 };
 use deckcraft_model::text::{
     Action, Align, Anchor, AutoFit, BodyProps, Bullet, Caps, Hyperlink, LevelStyle, ListStyle, ParaProps, Paragraph, Run, RunKind, RunProps, Spacing,
@@ -122,7 +122,13 @@ pub fn gradient(f: &El) -> Gradient {
         GradientShape::Linear { angle: 90.0, scaled: false }
     };
     let tile = f.child("tileRect").map(|r| [pct(r, "l"), pct(r, "t"), pct(r, "r"), pct(r, "b")].map(|v| v.unwrap_or(0.0).clamp(-10.0, 10.0)));
-    Gradient { tile: tile.unwrap_or_default(), stops, shape, rotate_with_shape: f.bool("rotWithShape").unwrap_or(true) }
+    Gradient {
+        tile: tile.unwrap_or_default(),
+        stops,
+        shape,
+        flip: f.attr("flip").and_then(GradientFlip::from_xml),
+        rotate_with_shape: f.bool("rotWithShape").unwrap_or(true),
+    }
 }
 
 /// `blipFill` (either `a:` or `p:`) → picture fill, registering the image as media.
diff --git a/crates/pptx/src/write/dml.rs b/crates/pptx/src/write/dml.rs
index 518f8c4a..aeae9801 100644
--- a/crates/pptx/src/write/dml.rs
+++ b/crates/pptx/src/write/dml.rs
@@ -1,7 +1,9 @@
 //! DrawingML writing: colours, fills, lines, effects, transforms and text.
 
 use deckcraft_geom::{Xfrm, pt_to_emu};
-use deckcraft_model::style::{ColorBase, ColorRef, Compound, Dash, Effects, Fill, GradientShape, Line, LineCap, LineJoin, PictureFill, PictureMode};
+use deckcraft_model::style::{
+    ColorBase, ColorRef, Compound, Dash, Effects, Fill, GradientFlip, GradientShape, Line, LineCap, LineJoin, PictureFill, PictureMode,
+};
 use deckcraft_model::text::{
     Action, AutoFit, BodyProps, Bullet, Caps, Hyperlink, ListStyle, ParaProps, Paragraph, RunKind, RunProps, Spacing, Strike, TextBody,
 };
@@ -279,7 +281,7 @@ fn shadow(w: &mut W, tag: &str, s: &deckcraft_model::style::Shadow) {
 }
 
 fn gradient(w: &mut W, g: &deckcraft_model::style::Gradient) {
-    w.open("a:gradFill", A::new().a("rotWithShape", if g.rotate_with_shape { "1" } else { "0" }));
+    w.open("a:gradFill", A::new().o("flip", g.flip.map(GradientFlip::xml)).a("rotWithShape", if g.rotate_with_shape { "1" } else { "0" }));
     // No stops: no `a:gsLst`, so the gradient keeps taking them from its style's fill.
     let mut stops = g.stops.clone();
     if stops.len() == 1 {
diff --git a/crates/pptx/tests/it/corpus_style.rs b/crates/pptx/tests/it/corpus_style.rs
index 6eac7bdd..42289760 100644
--- a/crates/pptx/tests/it/corpus_style.rs
+++ b/crates/pptx/tests/it/corpus_style.rs
@@ -46,6 +46,8 @@ fn gradient(angle: f64) -> Fill {
         shape: GradientShape::Linear { angle, scaled: true },
         rotate_with_shape: true,
         tile: [0.0; 4],
+
+        flip: None,
     })
 }
 
@@ -116,6 +118,8 @@ fn style_deck() -> Presentation {
         shape: GradientShape::Path { path: "circle".into(), focus: [0.2, 0.2, 0.2, 0.2] },
         rotate_with_shape: false,
         tile: [0.0; 4],
+
+        flip: None,
     }));
 
     let mut patt = shape(&mut p, "Pattern", 200.0, 260.0, 120.0, 80.0);
diff --git a/crates/pptx/tests/it/fills.rs b/crates/pptx/tests/it/fills.rs
index 98069d11..51bd51de 100644
--- a/crates/pptx/tests/it/fills.rs
+++ b/crates/pptx/tests/it/fills.rs
@@ -88,7 +88,8 @@ fn a_gradient_without_stops_is_saved_without_stops() {
     let mut p = defaults::new_presentation(None);
     let id = ShapeId(p.alloc_id().expect("ids"));
     let first = p.slides[0].id;
-    let own = Gradient { tile: [0.0; 4], stops: vec![], shape: GradientShape::Linear { angle: 45.0, scaled: true }, rotate_with_shape: true };
+    let own =
+        Gradient { tile: [0.0; 4], stops: vec![], shape: GradientShape::Linear { angle: 45.0, scaled: true }, rotate_with_shape: true, flip: None };
     p.slide_mut(first).expect("slide").shapes.push(Shape {
         id,
         name: "Styled".into(),
@@ -119,6 +120,8 @@ fn a_fill_overlay_round_trips() {
             ],
             shape: GradientShape::Linear { angle: 4.5, scaled: true },
             rotate_with_shape: true,
+
+            flip: None,
         }),
     };
     p.slide_mut(first).expect("slide").shapes.push(Shape {
@@ -148,6 +151,8 @@ fn a_gradient_tile_rect_is_read_and_round_trips() {
         shape: GradientShape::Path { path: "circle".into(), focus: [0.0, 0.0, 1.0, 1.0] },
         rotate_with_shape: true,
         tile: [-1.0, -1.0, 0.0, 0.0],
+
+        flip: None,
     };
     let mut p = defaults::new_presentation(None);
     let id = ShapeId(p.alloc_id().expect("ids"));
diff --git a/crates/pptx/tests/it/roundtrip.rs b/crates/pptx/tests/it/roundtrip.rs
index 370cc9a9..98516310 100644
--- a/crates/pptx/tests/it/roundtrip.rs
+++ b/crates/pptx/tests/it/roundtrip.rs
@@ -7,8 +7,8 @@ use deckcraft_geom::Xfrm;
 use deckcraft_model::anim::{AnimClass, AnimStart, Animation, TextBuild, Transition};
 use deckcraft_model::chart::{Chart, ChartType};
 use deckcraft_model::style::{
-    ColorRef, Dash, Effects, Fill, Glow, Gradient, GradientShape, GradientStop, Line, LineEnd, PatternFill, PictureAdjust, PictureFill, PictureMode,
-    Shadow,
+    ColorRef, Dash, Effects, Fill, Glow, Gradient, GradientFlip, GradientShape, GradientStop, Line, LineEnd, PatternFill, PictureAdjust, PictureFill,
+    PictureMode, Shadow,
 };
 use deckcraft_model::table::Table;
 use deckcraft_model::text::{
@@ -115,6 +115,8 @@ pub fn rich_deck() -> Presentation {
         ],
         shape: GradientShape::Linear { angle: 45.0, scaled: false },
         rotate_with_shape: true,
+
+        flip: Some(GradientFlip::Xy),
     }));
     a.line = Some(Line { width: Some(3.0), dash: Some(Dash::Preset { name: "dash".into() }), ..Line::solid(ColorRef::rgb(Rgba::rgb(0, 0, 0)), 3.0) });
     a.effects = Some(Effects {
@@ -488,6 +490,14 @@ fn shapes_fills_lines_effects_round_trip() {
     assert_eq!(by_name(&q.slides[1], "Group").id, by_name(&p.slides[1], "Group").id);
 }
 
+#[test]
+fn gradient_flip_mode_survives_two_pptx_round_trips() {
+    let p = rich_deck();
+    let q = round(&round(&p));
+    let gradient = by_name(&q.slides[1], "Gradient Star").fill.as_ref();
+    assert!(matches!(gradient, Some(Fill::Gradient(g)) if g.flip == Some(GradientFlip::Xy)));
+}
+
 #[test]
 fn pictures_media_and_ink_round_trip() {
     let p = rich_deck();
diff --git a/crates/render/src/tests.rs b/crates/render/src/tests.rs
index db8644ab..ad6b9424 100644
--- a/crates/render/src/tests.rs
+++ b/crates/render/src/tests.rs
@@ -978,6 +978,8 @@ fn a_linear_gradient_ramps_like_powerpoint() {
             stops: vec![stop(0.0, deckcraft_color::Rgba::rgb(0, 0, 0)), stop(1.0, deckcraft_color::Rgba::rgb(255, 255, 255))],
             shape: GradientShape::Linear { angle: 0.0, scaled: false },
             rotate_with_shape: true,
+
+            flip: None,
         })),
         line: Some(deckcraft_model::style::Line { fill: Some(Fill::None), ..Default::default() }),
         ..Default::default()
@@ -1003,6 +1005,8 @@ fn a_gradient_with_a_stop_off_the_end_stays_linear() {
             stops: vec![stop(0.2, deckcraft_color::Rgba::rgb(0, 0, 0)), stop(1.0, deckcraft_color::Rgba::rgb(255, 255, 255))],
             shape: GradientShape::Linear { angle: 0.0, scaled: false },
             rotate_with_shape: true,
+
+            flip: None,
         })),
         line: Some(deckcraft_model::style::Line { fill: Some(Fill::None), ..Default::default() }),
         ..Default::default()
@@ -1044,6 +1048,8 @@ fn a_shape_filled_with_the_background_shows_the_slide_background() {
             stops: vec![stop(0.0, 0), stop(0.5, 0), stop(1.0, 200)],
             shape: GradientShape::Linear { angle: 0.0, scaled: false },
             rotate_with_shape: true,
+
+            flip: None,
         }),
     });
     let img = render_slide(&p, 0, &RenderOpts { scale: 1.0, ..Default::default() });
@@ -1145,6 +1151,8 @@ fn a_text_gradient_starts_over_on_every_line() {
             stops: vec![stop(0.0, 0), stop(1.0, 255)],
             shape: GradientShape::Linear { angle: 90.0, scaled: false },
             rotate_with_shape: true,
+
+            flip: None,
         }));
     }
     sh.text = Some(t);
@@ -1306,6 +1314,8 @@ fn rect_path_gradients_draw_x_shaped_contours() {
             stops: vec![stop(0.0, 0), stop(0.5, 128), stop(1.0, 255)],
             shape: GradientShape::Path { path: "rect".into(), focus: [0.5, 0.5, 0.5, 0.5] },
             rotate_with_shape: true,
+
+            flip: None,
         })),
         line: Some(deckcraft_model::style::Line { fill: Some(Fill::None), ..Default::default() }),
         ..Default::default()
diff --git a/crates/render/src/tests_wild.rs b/crates/render/src/tests_wild.rs
index fb561346..c73987af 100644
--- a/crates/render/src/tests_wild.rs
+++ b/crates/render/src/tests_wild.rs
@@ -186,6 +186,8 @@ fn radial(focus: [f64; 4]) -> Shape {
             stops,
             shape: GradientShape::Path { path: "circle".into(), focus },
             rotate_with_shape: true,
+
+            flip: None,
         })),
         line: no_line(),
         ..Default::default()
@@ -310,8 +312,13 @@ fn a_pictures_border_lies_outside_the_picture() {
 fn children_filled_with_the_group_fill_show_one_fill_across_the_group() {
     use deckcraft_model::style::{Gradient, GradientShape, GradientStop};
     let stops = vec![GradientStop { pos: 0.0, color: ColorRef::rgb(RED) }, GradientStop { pos: 1.0, color: ColorRef::rgb(Rgba::rgb(0, 0, 255)) }];
-    let grad =
-        Fill::Gradient(Gradient { tile: [0.0; 4], stops, shape: GradientShape::Linear { angle: 0.0, scaled: false }, rotate_with_shape: true });
+    let grad = Fill::Gradient(Gradient {
+        tile: [0.0; 4],
+        stops,
+        shape: GradientShape::Linear { angle: 0.0, scaled: false },
+        rotate_with_shape: true,
+        flip: None,
+    });
     let child = |id: u32, x: f64| Shape {
         id: ShapeId(id),
         xfrm: Some(Xfrm::new(x, 0.0, 90.0, 100.0)),
@@ -372,7 +379,13 @@ fn a_linear_gradient_spans_its_tile_rect() {
     use deckcraft_model::style::{Gradient, GradientShape, GradientStop};
     // Tile rect the left half of the box: the ramp ends half way and stays black after.
     let stops = vec![GradientStop { pos: 0.0, color: ColorRef::rgb(WHITE) }, GradientStop { pos: 1.0, color: ColorRef::rgb(Rgba::BLACK) }];
-    let g = Gradient { stops, shape: GradientShape::Linear { angle: 0.0, scaled: false }, rotate_with_shape: true, tile: [0.0, 0.0, 0.5, 0.0] };
+    let g = Gradient {
+        stops,
+        shape: GradientShape::Linear { angle: 0.0, scaled: false },
+        rotate_with_shape: true,
+        tile: [0.0, 0.0, 0.5, 0.0],
+        flip: None,
+    };
     let sh = Shape {
         id: ShapeId(20),
         xfrm: Some(Xfrm::new(100.0, 100.0, 400.0, 100.0)),
@@ -502,6 +515,8 @@ fn gradient_lines_and_their_heads_take_the_gradient() {
             shape: GradientShape::Linear { angle, scaled: false },
             rotate_with_shape: true,
             tile: [0.0; 4],
+
+            flip: None,
         })
     };
     // Left to right along a 20 pt line: red at its start, blue at its end, and the arrowhead at
@@ -656,6 +671,8 @@ fn a_gradient_not_rotating_with_its_shape_keeps_to_the_slide() {
             shape: GradientShape::Linear { angle: 0.0, scaled: false },
             rotate_with_shape,
             tile: [0.0; 4],
+
+            flip: None,
         };
         // 200 × 100 turned a quarter: it covers 150..250 across and 50..250 down.
         let sh = Shape {
diff --git a/crates/ui-egui/src/panels/fillui.rs b/crates/ui-egui/src/panels/fillui.rs
index 5150b8f0..06b1ac93 100644
--- a/crates/ui-egui/src/panels/fillui.rs
+++ b/crates/ui-egui/src/panels/fillui.rs
@@ -21,6 +21,8 @@ pub fn default_gradient(base: ColorRef, angle: f64) -> Gradient {
         stops: vec![GradientStop { pos: 0.0, color: base }, GradientStop { pos: 1.0, color: dark }],
         shape: GradientShape::Linear { angle, scaled: false },
         rotate_with_shape: true,
+
+        flip: None,
     }
 }
 
@@ -142,6 +144,8 @@ pub fn gradient_editor(ui: &mut Ui, id: &str, g: &Gradient, sc: &ColorScheme) ->
                 stops: vec![GradientStop { pos: 0.0, color: light }, GradientStop { pos: 1.0, color: dark }],
                 shape: GradientShape::Path { path: "circle".into(), focus: [0.5, 0.5, 0.5, 0.5] },
                 rotate_with_shape: true,
+
+                flip: None,
             },
             Gradient {
                 stops: vec![GradientStop { pos: 0.0, color: base.clone() }, GradientStop { pos: 1.0, color: with_alpha(base, 0.0) }],