diff --git a/web/libs/editor/src/common/TextArea/TextArea.tsx b/web/libs/editor/src/common/TextArea/TextArea.tsx
index 77ed4c550cdd..542aa2afb666 100644
--- a/web/libs/editor/src/common/TextArea/TextArea.tsx
+++ b/web/libs/editor/src/common/TextArea/TextArea.tsx
@@ -24,6 +24,8 @@ export type TextAreaProps = {
   placeholder?: string;
   name?: string;
   id?: string;
+  "aria-label"?: string;
+  "data-testid"?: string;
 };
 
 export const TextArea: FC<TextAreaProps> = ({
diff --git a/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.prefix.css b/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.prefix.css
index 1b9a6c56b4e6..bebce7e2c953 100644
--- a/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.prefix.css
+++ b/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.prefix.css
@@ -85,16 +85,43 @@
 
 .relation-meta {
   display: flex;
+  flex-direction: column;
+  gap: 8px;
   padding-left: 64px;
+  padding-right: 8px;
   padding-bottom: 5px;
-  align-items: center;
+  align-items: stretch;
 
   &__title {
     flex: none;
     padding-right: 8px;
   }
 
+  &__field {
+    display: flex;
+    flex-direction: column;
+    gap: 4px;
+  }
+
+  &__label {
+    color: var(--color-neutral-content-subtle);
+    font-size: 12px;
+    line-height: 16px;
+  }
+
   &__select {
     flex: 1;
   }
+
+  &__note {
+    width: 100%;
+    min-height: 48px !important;
+    padding: 6px 8px !important;
+    border: 1px solid var(--color-neutral-border) !important;
+    border-radius: 4px !important;
+    background-color: var(--color-neutral-background) !important;
+    color: var(--color-neutral-content) !important;
+    font-size: 12px !important;
+    line-height: 18px !important;
+  }
 }
diff --git a/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.tsx b/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.tsx
index 746cea682311..32e0f071aab4 100644
--- a/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.tsx
+++ b/web/libs/editor/src/components/SidePanels/DetailsPanel/Relations.tsx
@@ -10,6 +10,7 @@ import {
 import { Button, Select } from "@humansignal/ui";
 import { observer } from "mobx-react";
 import { type FC, useCallback, useMemo, useState } from "react";
+import { TextArea } from "../../../common/TextArea/TextArea";
 import { cn } from "../../../utils/bem";
 import { wrapArray } from "../../../utils/utilities";
 import { RegionItem } from "./RegionItem";
@@ -91,10 +92,10 @@ const RelationItem: FC<{ relation: any }> = observer(({ relation }) => {
         </div>
         <div className={cn("relations").elem("actions").toClassName()}>
           <div className={cn("relations").elem("action").toClassName()}>
-            {(hovered || relation.showMeta) && relation.hasRelations && (
+            {(hovered || relation.showMeta) && (
               <Button
                 primary={relation.showMeta}
-                aria-label={`${relation.showMeta ? "Hide" : "Show"} Relation Labels`}
+                aria-label={`${relation.showMeta ? "Hide" : "Show"} Relation Details`}
                 type={relation.showMeta ? undefined : "text"}
                 onClick={relation.toggleMeta}
                 style={{ padding: 0 }}
@@ -148,7 +149,7 @@ const RelationItem: FC<{ relation: any }> = observer(({ relation }) => {
 
 const RelationMeta: FC<any> = observer(({ relation }) => {
   const { selectedValues, control } = relation;
-  const { children, choice } = control;
+  const { children = [], choice } = control ?? {};
 
   const selectionMode = useMemo(() => {
     return choice === "multiple";
@@ -171,16 +172,43 @@ const RelationMeta: FC<any> = observer(({ relation }) => {
     [children],
   );
 
+  const onNoteInput = useCallback(
+    (value: string) => {
+      relation.setNote(value);
+    },
+    [relation],
+  );
+
   return (
     <div className={cn("relation-meta").toClassName()}>
-      <Select
-        multiple={selectionMode}
-        style={{ width: "100%" }}
-        placeholder="Select labels"
-        value={selectedValues}
-        onChange={onChange}
-        options={options}
-      />
+      {relation.hasRelations && (
+        <div className={cn("relation-meta").elem("field").toClassName()}>
+          <Select
+            multiple={selectionMode}
+            style={{ width: "100%" }}
+            placeholder="Select labels"
+            value={selectedValues}
+            onChange={onChange}
+            options={options}
+          />
+        </div>
+      )}
+      <div className={cn("relation-meta").elem("field").toClassName()}>
+        <label className={cn("relation-meta").elem("label").toClassName()} htmlFor={`relation-note-${relation.id}`}>
+          Note
+        </label>
+        <TextArea
+          id={`relation-note-${relation.id}`}
+          className={cn("relation-meta").elem("note").toClassName()}
+          placeholder="Add a note"
+          value={relation.note}
+          rows={2}
+          maxRows={6}
+          aria-label="Relation note"
+          data-testid="relation-note"
+          onInput={onNoteInput}
+        />
+      </div>
     </div>
   );
 });
diff --git a/web/libs/editor/src/components/SidePanels/DetailsPanel/__tests__/Relations.test.tsx b/web/libs/editor/src/components/SidePanels/DetailsPanel/__tests__/Relations.test.tsx
new file mode 100644
index 000000000000..c3a4d590a72c
--- /dev/null
+++ b/web/libs/editor/src/components/SidePanels/DetailsPanel/__tests__/Relations.test.tsx
@@ -0,0 +1,110 @@
+import { fireEvent, render, screen } from "@testing-library/react";
+import "@testing-library/jest-dom";
+import { Relations } from "../Relations";
+
+jest.mock("mobx-react", () => ({
+  observer: (component: any) => component,
+}));
+
+jest.mock("@humansignal/icons", () => ({
+  IconEyeClosed: () => <span data-testid="icon-eye-closed" />,
+  IconEyeOpened: () => <span data-testid="icon-eye-opened" />,
+  IconMenu: () => <span data-testid="icon-menu" />,
+  IconRelationBi: () => <span data-testid="icon-relation-bi" />,
+  IconRelationLeft: () => <span data-testid="icon-relation-left" />,
+  IconRelationRight: () => <span data-testid="icon-relation-right" />,
+  IconTrash: () => <span data-testid="icon-trash" />,
+}));
+
+jest.mock("@humansignal/ui", () => ({
+  Button: ({ children, onClick, primary, type, ...props }: any) => (
+    <button type="button" data-primary={primary ? "true" : "false"} onClick={onClick} {...props}>
+      {children}
+    </button>
+  ),
+  Select: ({ onChange, options = [], value, multiple, placeholder }: any) => (
+    <select
+      aria-label={placeholder}
+      multiple={multiple}
+      value={multiple ? value : (value?.[0] ?? "")}
+      onChange={(event) => onChange(event.target.value)}
+    >
+      <option value="" />
+      {options.map((option: any) => (
+        <option key={option.value} value={option.value}>
+          {option.value}
+        </option>
+      ))}
+    </select>
+  ),
+}));
+
+jest.mock("../RegionItem", () => ({
+  RegionItem: ({ region }: any) => <div data-testid="region-item">{region.id}</div>,
+}));
+
+const makeRelation = (overrides: any = {}) => ({
+  id: "relation-1",
+  direction: "right",
+  visible: true,
+  showMeta: true,
+  hasRelations: true,
+  note: "Existing note",
+  selectedValues: ["supports"],
+  control: {
+    choice: "single",
+    children: [{ value: "supports", background: "#fff" }],
+  },
+  node1: { id: "region-1", setHighlight: jest.fn(), toggleHighlight: jest.fn() },
+  node2: { id: "region-2", setHighlight: jest.fn(), toggleHighlight: jest.fn() },
+  parent: { deleteRelation: jest.fn() },
+  rotateDirection: jest.fn(),
+  toggleMeta: jest.fn(),
+  toggleVisibility: jest.fn(),
+  toggleHighlight: jest.fn(),
+  setSelfHighlight: jest.fn(),
+  setRelations: jest.fn(),
+  setNote: jest.fn(),
+  ...overrides,
+});
+
+describe("Relations", () => {
+  beforeAll(() => {
+    Object.defineProperty(global, "ResizeObserver", {
+      writable: true,
+      value: jest.fn().mockImplementation(() => ({
+        observe: jest.fn(),
+        unobserve: jest.fn(),
+        disconnect: jest.fn(),
+      })),
+    });
+  });
+
+  it("renders and updates a relation note", () => {
+    const relation = makeRelation();
+
+    render(<Relations relationStore={{ orderedRelations: [relation] }} />);
+
+    const note = screen.getByLabelText("Relation note");
+
+    expect(note).toHaveValue("Existing note");
+
+    fireEvent.input(note, { target: { value: "Updated relationship note" } });
+
+    expect(relation.setNote).toHaveBeenCalledWith("Updated relationship note");
+  });
+
+  it("shows relation details even without configured relation labels", () => {
+    const relation = makeRelation({
+      hasRelations: false,
+      selectedValues: [],
+      control: { children: [] },
+    });
+
+    render(<Relations relationStore={{ orderedRelations: [relation] }} />);
+
+    expect(screen.queryByLabelText("Select labels")).not.toBeInTheDocument();
+    expect(screen.getByLabelText("Relation note")).toBeInTheDocument();
+    expect(screen.getByRole("button", { name: "Hide Relation Details" })).toBeInTheDocument();
+  });
+});
diff --git a/web/libs/editor/src/stores/Annotation/Annotation.js b/web/libs/editor/src/stores/Annotation/Annotation.js
index 2a08ad9b892a..9fefeab3252d 100644
--- a/web/libs/editor/src/stores/Annotation/Annotation.js
+++ b/web/libs/editor/src/stores/Annotation/Annotation.js
@@ -1266,6 +1266,7 @@ const _Annotation = types
               `${obj.to_id}#${self.id}`,
               obj.direction,
               obj.labels,
+              obj.note,
             );
           }
         }
diff --git a/web/libs/editor/src/stores/RelationStore.js b/web/libs/editor/src/stores/RelationStore.js
index 6b7343d90ff2..679862bf9e31 100644
--- a/web/libs/editor/src/stores/RelationStore.js
+++ b/web/libs/editor/src/stores/RelationStore.js
@@ -23,6 +23,8 @@ const Relation = types
 
     // labels
     labels: types.maybeNull(types.array(types.string)),
+
+    note: types.optional(types.string, ""),
   })
   .volatile(() => ({
     showMeta: false,
@@ -101,6 +103,10 @@ const Relation = types
     setRelations(values) {
       self.labels = values;
     },
+
+    setNote(value) {
+      self.note = value;
+    },
   }));
 
 const RelationStore = types
@@ -212,18 +218,20 @@ const RelationStore = types
         };
 
         if (r.selectedValues) s.labels = r.selectedValues;
+        if (r.note) s.note = r.note;
 
         return s;
       });
     },
 
-    deserializeRelation(node1, node2, direction, labels) {
+    deserializeRelation(node1, node2, direction, labels, note) {
       const rl = self.addRelation(node1, node2);
 
       if (!rl) return; // duplicated relation
 
       rl.direction = direction;
       rl.labels = labels;
+      rl.note = note ?? "";
     },
 
     toggleConnections() {
diff --git a/web/libs/editor/src/stores/__tests__/RelationStore.test.js b/web/libs/editor/src/stores/__tests__/RelationStore.test.js
index d0c5b0118242..3323893889c3 100644
--- a/web/libs/editor/src/stores/__tests__/RelationStore.test.js
+++ b/web/libs/editor/src/stores/__tests__/RelationStore.test.js
@@ -227,6 +227,15 @@ describe("RelationStore", () => {
       expect(ser[0].labels).toEqual(["parent"]);
     });
 
+    it("serialize includes note when relation has a note", () => {
+      const { relationStore, regions } = createStoreWithTwoRectRegionsAndRelations();
+      const [r1, r2] = regions;
+      const rl = relationStore.addRelation(r1, r2);
+      rl.setNote("Review this relationship");
+      const ser = relationStore.serialize();
+      expect(ser[0].note).toBe("Review this relationship");
+    });
+
     it("deserializeRelation adds relation with direction and labels", () => {
       const { relationStore, regions } = createStoreWithTwoRectRegionsAndRelations();
       const [r1, r2] = regions;
@@ -237,6 +246,14 @@ describe("RelationStore", () => {
       expect(rl.labels).toEqual(["child"]);
     });
 
+    it("deserializeRelation restores note", () => {
+      const { relationStore, regions } = createStoreWithTwoRectRegionsAndRelations();
+      const [r1, r2] = regions;
+      relationStore.deserializeRelation(r1, r2, "left", ["child"], "Needs reviewer context");
+      const rl = relationStore.relations[0];
+      expect(rl.note).toBe("Needs reviewer context");
+    });
+
     it("deserializeRelation does nothing when relation already exists", () => {
       const { relationStore, regions } = createStoreWithTwoRectRegionsAndRelations();
       const [r1, r2] = regions;
@@ -438,6 +455,14 @@ describe("Relation (model)", () => {
       expect(rl.labels).toEqual(["parent", "child"]);
     });
 
+    it("setNote updates note", () => {
+      const { relationStore, regions } = createStoreWithTwoRectRegionsAndRelations();
+      const [r1, r2] = regions;
+      const rl = relationStore.addRelation(r1, r2);
+      rl.setNote("This relationship is uncertain");
+      expect(rl.note).toBe("This relationship is uncertain");
+    });
+
     it("toggleVisibility toggles visible", () => {
       const { relationStore, regions } = createStoreWithTwoRectRegionsAndRelations();
       const [r1, r2] = regions;