diff --git a/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/ChecklistOptionGroup.tsx b/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/ChecklistOptionGroup.tsx
index 0a3397b058..d8f211eee0 100644
--- a/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/ChecklistOptionGroup.tsx
+++ b/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/ChecklistOptionGroup.tsx
@@ -1,24 +1,25 @@
 import Box from "@mui/material/Box";
+import Grid from "@mui/material/Grid";
+import Typography from "@mui/material/Typography";
 import { Group } from "@planx/components/Checklist/model";
 import { FormikProps } from "formik";
 import { partition } from "lodash";
 import React from "react";
 import { ExpandableListItem } from "ui/public/ExpandableList";
+import FormWrapper from "ui/public/FormWrapper";
 import ChecklistItem from "ui/shared/ChecklistItem/ChecklistItem";
 
 import { Option } from "../../../../shared";
 import { toggleNonExclusiveCheckbox } from "../../helpers";
-import { useExclusiveOption } from "../../hooks/useExclusiveOption";
-import { ExclusiveChecklistItem } from "../ExclusiveChecklistItem";
+import { useExclusiveOptionInGroupedChecklists } from "../../hooks/useExclusiveOption";
 
 interface Props {
   group: Group<Option>;
   index: number;
   isExpanded: boolean;
   formik: FormikProps<{
-    checked: Array<string>;
+    checked: Record<string, Array<string>>;
   }>;
-  setCheckedFieldValue: (optionIds: string[]) => void;
   toggleGroup: (index: number) => void;
 }
 
@@ -27,7 +28,6 @@ export const ChecklistOptionGroup = ({
   index,
   isExpanded,
   formik,
-  setCheckedFieldValue,
   toggleGroup,
 }: Props) => {
   const [exclusiveOptions, nonExclusiveOptions]: Option[][] = partition(
@@ -35,20 +35,23 @@ export const ChecklistOptionGroup = ({
     (option: Option) => option.data.exclusive
   );
 
-  const { exclusiveOrOption, toggleExclusiveCheckbox } = useExclusiveOption(
-    exclusiveOptions,
-    formik
-  );
+  const { exclusiveOrOption, toggleExclusiveCheckbox } =
+    useExclusiveOptionInGroupedChecklists(
+      exclusiveOptions,
+      group.title,
+      formik
+    );
 
   const changeCheckbox = (id: string) => () => {
-    const currentCheckedIds = formik.values.checked;
+    const allCheckedIds = formik.values.checked;
+    const currentCheckedIds = allCheckedIds[group.title];
 
     const currentCheckboxIsExclusiveOption =
       exclusiveOrOption && id === exclusiveOrOption.id;
 
     if (currentCheckboxIsExclusiveOption) {
       const newCheckedIds = toggleExclusiveCheckbox(id);
-      setCheckedFieldValue(newCheckedIds);
+      formik.setFieldValue("checked", newCheckedIds);
       return;
     }
     const newCheckedIds = toggleNonExclusiveCheckbox(
@@ -56,7 +59,10 @@ export const ChecklistOptionGroup = ({
       currentCheckedIds,
       exclusiveOrOption
     );
-    setCheckedFieldValue(newCheckedIds);
+
+    allCheckedIds[group.title] = newCheckedIds;
+
+    formik.setFieldValue("checked", allCheckedIds);
   };
 
   return (
@@ -81,15 +87,26 @@ export const ChecklistOptionGroup = ({
             key={option.data.text}
             label={option.data.text}
             id={option.id}
-            checked={formik.values.checked.includes(option.id)}
+            checked={formik.values.checked[group.title].includes(option.id)}
           />
         ))}
         {exclusiveOrOption && (
-          <ExclusiveChecklistItem
-            exclusiveOrOption={exclusiveOrOption}
-            changeCheckbox={changeCheckbox}
-            formik={formik}
-          />
+          // Exclusive or option
+          <FormWrapper key={exclusiveOrOption.id}>
+            <Grid item xs={12} key={exclusiveOrOption.data.text}>
+              <Typography width={36} display="flex" justifyContent="center">
+                or
+              </Typography>
+              <ChecklistItem
+                onChange={changeCheckbox(exclusiveOrOption.id)}
+                label={exclusiveOrOption.data.text}
+                id={exclusiveOrOption.id}
+                checked={formik.values.checked[group.title].includes(
+                  exclusiveOrOption.id
+                )}
+              />
+            </Grid>
+          </FormWrapper>
         )}
       </Box>
     </ExpandableListItem>
diff --git a/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklist.tsx b/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklist.tsx
index 5cc8cb6287..c94d7fe0cd 100644
--- a/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklist.tsx
+++ b/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklist.tsx
@@ -1,6 +1,9 @@
 import Grid from "@mui/material/Grid";
 import { visuallyHidden } from "@mui/utils";
-import { checklistValidationSchema } from "@planx/components/Checklist/model";
+import {
+  getLayout,
+  groupedChecklistValidationSchema,
+} from "@planx/components/Checklist/model";
 import Card from "@planx/components/shared/Preview/Card";
 import { CardHeader } from "@planx/components/shared/Preview/CardHeader/CardHeader";
 import { getIn, useFormik } from "formik";
@@ -10,7 +13,6 @@ import ErrorWrapper from "ui/shared/ErrorWrapper";
 import { object } from "yup";
 
 import { PublicChecklistProps } from "../../../types";
-import { useSortedOptions } from "../../hooks/useSortedOptions";
 import { ChecklistLayout } from "../VisibleChecklist";
 import { GroupedChecklistOptions } from "./GroupedChecklistOptions";
 
@@ -29,25 +31,34 @@ export const GroupedChecklist: React.FC<PublicChecklistProps> = (props) => {
     id,
   } = props;
 
-  const formik = useFormik<{ checked: Array<string> }>({
+  const formik = useFormik<{ checked: Record<string, Array<string>> }>({
     initialValues: {
-      checked: previouslySubmittedData?.answers || [],
+      // e.g. { 'Section 1': [], 'Section 2': [ 'S2_Option2' ] }
+      checked:
+        groupedOptions?.reduce(
+          (acc, group) => ({
+            ...acc,
+            [group.title]:
+              previouslySubmittedData?.answers?.filter((id) =>
+                group.children.some((item) => item.id === id)
+              ) || [],
+          }),
+          {}
+        ) || {},
     },
     onSubmit: (values) => {
-      handleSubmit?.({ answers: values.checked });
+      const flattenedCheckedIds = Object.values(values.checked).flat();
+      handleSubmit?.({ answers: flattenedCheckedIds });
     },
     validateOnBlur: false,
     validateOnChange: false,
     validationSchema: object({
-      checked: checklistValidationSchema(props),
+      checked: groupedChecklistValidationSchema(props),
     }),
   });
 
-  const { setCheckedFieldValue, layout } = useSortedOptions(
-    options,
-    groupedOptions,
-    formik
-  );
+  // TODO: do we need useSortedOptions ?
+  const layout = getLayout({ options, groupedOptions });
 
   return (
     <Card handleSubmit={formik.handleSubmit} isValid>
@@ -71,7 +82,6 @@ export const GroupedChecklist: React.FC<PublicChecklistProps> = (props) => {
               <GroupedChecklistOptions
                 groupedOptions={groupedOptions}
                 previouslySubmittedData={previouslySubmittedData}
-                setCheckedFieldValue={setCheckedFieldValue}
                 formik={formik}
               />
             )}
diff --git a/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklistOptions.tsx b/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklistOptions.tsx
index 3bd2fe07bc..1cab924fa7 100644
--- a/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklistOptions.tsx
+++ b/editor.planx.uk/src/@planx/components/Checklist/Public/components/grouped/GroupedChecklistOptions.tsx
@@ -13,14 +13,12 @@ import { ChecklistOptionGroup } from "./ChecklistOptionGroup";
 interface GroupedChecklistOptionsProps {
   groupedOptions: Group<Option>[];
   previouslySubmittedData: Store.UserData | undefined;
-  setCheckedFieldValue: (optionIds: string[]) => void;
-  formik: FormikProps<{ checked: Array<string> }>;
+  formik: FormikProps<{ checked: Record<string, Array<string>> }>;
 }
 
 export const GroupedChecklistOptions = ({
   groupedOptions,
   previouslySubmittedData,
-  setCheckedFieldValue,
   formik,
 }: GroupedChecklistOptionsProps) => {
   const { expandedGroups, toggleGroup } = useExpandedGroups(
@@ -42,7 +40,6 @@ export const GroupedChecklistOptions = ({
                 isExpanded={isExpanded}
                 index={index}
                 formik={formik}
-                setCheckedFieldValue={setCheckedFieldValue}
                 toggleGroup={toggleGroup}
               />
             );
diff --git a/editor.planx.uk/src/@planx/components/Checklist/Public/hooks/useExclusiveOption.tsx b/editor.planx.uk/src/@planx/components/Checklist/Public/hooks/useExclusiveOption.tsx
index 85dd1d0a4f..a8457870ce 100644
--- a/editor.planx.uk/src/@planx/components/Checklist/Public/hooks/useExclusiveOption.tsx
+++ b/editor.planx.uk/src/@planx/components/Checklist/Public/hooks/useExclusiveOption.tsx
@@ -11,7 +11,7 @@ export const useExclusiveOption = (
   const exclusiveOptionIsChecked =
     exclusiveOrOption && formik.values.checked.includes(exclusiveOrOption.id);
 
-  const toggleExclusiveCheckbox = (checkboxId: string) => {
+  const toggleExclusiveCheckbox = (checkboxId: string): Array<string> => {
     return exclusiveOptionIsChecked ? [] : [checkboxId];
   };
 
@@ -21,3 +21,38 @@ export const useExclusiveOption = (
     toggleExclusiveCheckbox,
   };
 };
+
+export const useExclusiveOptionInGroupedChecklists = (
+  exclusiveOptions: Option[],
+  checklistGroupTitle: string,
+  formik: FormikProps<{ checked: Record<string, Array<string>> }>
+) => {
+  const [exclusiveOrOption] = exclusiveOptions;
+
+  const exclusiveOptionIsChecked =
+    exclusiveOrOption &&
+    formik.values.checked[checklistGroupTitle] &&
+    formik.values.checked[checklistGroupTitle].includes(exclusiveOrOption.id);
+
+  const toggleExclusiveCheckbox = (
+    checkboxId: string
+  ): Record<string, Array<string>> => {
+    const newCheckedIds = formik.values.checked;
+    if (exclusiveOptionIsChecked) {
+      if (checklistGroupTitle in formik.values.checked) {
+        // empty the array in this checklist section only
+        newCheckedIds[checklistGroupTitle] = [];
+      }
+    } else {
+      // add in the checkboxId at this index
+      newCheckedIds[checklistGroupTitle] = [checkboxId];
+    }
+    return newCheckedIds;
+  };
+
+  return {
+    exclusiveOrOption,
+    exclusiveOptionIsChecked,
+    toggleExclusiveCheckbox,
+  };
+};
diff --git a/editor.planx.uk/src/@planx/components/Checklist/Public/tests/Public.grouped.test.tsx b/editor.planx.uk/src/@planx/components/Checklist/Public/tests/Public.grouped.test.tsx
index 7690f7e471..21ce7028d7 100644
--- a/editor.planx.uk/src/@planx/components/Checklist/Public/tests/Public.grouped.test.tsx
+++ b/editor.planx.uk/src/@planx/components/Checklist/Public/tests/Public.grouped.test.tsx
@@ -72,23 +72,34 @@ describe("Checklist Component - Grouped Layout", () => {
       />
     );
 
+    // user presses exclusive option in section 1
     await user.click(screen.getByText("Section 1"));
-
-    const exclusiveOptionInSection1 = screen.getByText("S1 Option1");
-    const nonExclusiveOptionInSection1 = screen.getByText("S1 Option2");
-
+    const exclusiveOptionInSection1 = screen.getByLabelText("S1 Option1");
+    const nonExclusiveOptionInSection1 = screen.getByLabelText("S1 Option2");
     await user.click(exclusiveOptionInSection1);
+
     expect(exclusiveOptionInSection1).toHaveAttribute("checked");
 
+     // user presses non-exclusive option in section 1, exclusive option should uncheck.
     await user.click(nonExclusiveOptionInSection1);
     expect(exclusiveOptionInSection1).not.toHaveAttribute("checked");
     expect(nonExclusiveOptionInSection1).toHaveAttribute("checked");
 
+     // user presses exclusive option in section 3
     await user.click(screen.getByText("Section 3"));
+    const exclusiveOptionInSection3 = screen.getByLabelText("S3 Option2");
+    await user.click(exclusiveOptionInSection3);
+
+    // options in other checklists should not be affected
+    expect(exclusiveOptionInSection3).toHaveAttribute("checked");
+    expect(nonExclusiveOptionInSection1).toHaveAttribute("checked");
+
     // user presses two non-exclusive options in this section
     await user.click(screen.getByText("S3 Option1"));
     await user.click(screen.getByText("S3 Option3"));
 
+    expect(exclusiveOptionInSection3).not.toHaveAttribute("checked");
+
     await user.click(screen.getByTestId("continue-button"));
 
     expect(handleSubmit).toHaveBeenCalledWith({
@@ -161,5 +172,12 @@ describe("Checklist Component - Grouped Layout", () => {
     expect(handleSubmit).toHaveBeenCalledWith({
       answers: ["S2_Option1", "S2_Option2"],
     });
+    // expect(handleSubmit).toHaveBeenCalledWith({
+    //   answers: {
+    //     "Section 1": [],
+    //     "Section 2": ["S2_Option1", "S2_Option2"],
+    //     "Section 3": [],
+    //   },
+    // });
   });
 });
diff --git a/editor.planx.uk/src/@planx/components/Checklist/model.ts b/editor.planx.uk/src/@planx/components/Checklist/model.ts
index 67ab2f694c..305cfe8c9f 100644
--- a/editor.planx.uk/src/@planx/components/Checklist/model.ts
+++ b/editor.planx.uk/src/@planx/components/Checklist/model.ts
@@ -1,4 +1,4 @@
-import { array } from "yup";
+import { array, object, string } from "yup";
 
 import { BaseNodeData, Option } from "../shared";
 import { ChecklistLayout } from "./Public/components/VisibleChecklist";
@@ -126,3 +126,41 @@ export const checklistValidationSchema = ({
       },
     });
 };
+
+export const groupedChecklistValidationSchema = ({
+  allRequired,
+  options,
+  groupedOptions,
+}: Checklist) => {
+  const flatOptions = getFlatOptions({ options, groupedOptions });
+
+  return object()
+    .shape(
+      Object.fromEntries(
+        groupedOptions?.map((group) => [group.title, array().of(string())]) ||
+          []
+      )
+    )
+    .required()
+    .test({
+      name: "atLeastOneChecked",
+      message: "Select at least one option",
+      test: (value: Record<string, string[]>) => {
+        const arrayOfArrays = Object.values(value || {});
+        return arrayOfArrays.some((arr) => arr.length > 0);
+      },
+    })
+    .test({
+      name: "notAllChecked",
+      message: "All options must be checked",
+      test: (checked?: Record<string, string[]>) => {
+        if (!allRequired) {
+          return true;
+        }
+        const allChecked =
+          checked &&
+          Object.values(checked).flat().length === flatOptions.length;
+        return Boolean(allChecked);
+      },
+    });
+};