diff --git a/.github/workflows/Action-Test.yml b/.github/workflows/Action-Test.yml
index ec94308..fa34cd0 100644
--- a/.github/workflows/Action-Test.yml
+++ b/.github/workflows/Action-Test.yml
@@ -60,6 +60,25 @@ jobs:
           Name: PSModuleTest
           WorkingDirectory: tests/srcTestRepo
 
+      - name: Verify group overview pages publish as section index
+        shell: pwsh
+        run: |
+          $docs = 'tests/srcTestRepo/outputs/docs'
+          # PSModule: <Group>/<Group>.md mapped to index.md. SomethingElse: explicit index.md
+          # passthrough. Widgets: Index.md normalized to index.md (case-insensitive).
+          $expected = @('PSModule/index.md', 'SomethingElse/index.md', 'Widgets/index.md')
+          $unexpected = @('PSModule/PSModule.md', 'SomethingElse/SomethingElse.md', 'Widgets/Index.md')
+          $failed = $false
+          foreach ($rel in $expected) {
+              if (Test-Path (Join-Path $docs $rel)) { Write-Host "OK  present: $rel" }
+              else { Write-Host "ERR missing: $rel"; $failed = $true }
+          }
+          foreach ($rel in $unexpected) {
+              if (Test-Path (Join-Path $docs $rel)) { Write-Host "ERR should not exist: $rel"; $failed = $true }
+              else { Write-Host "OK  absent:  $rel" }
+          }
+          if ($failed) { throw 'Group overview pages were not published as section index (index.md).' }
+
       - name: Lint documentation
         uses: super-linter/super-linter/slim@4ce20838b8ab83717e78138c5b3a1407148e0918 # v8.7.0
         env:
diff --git a/src/helpers/Build-PSModuleDocumentation.ps1 b/src/helpers/Build-PSModuleDocumentation.ps1
index e6387c7..5b8ab20 100644
--- a/src/helpers/Build-PSModuleDocumentation.ps1
+++ b/src/helpers/Build-PSModuleDocumentation.ps1
@@ -224,13 +224,48 @@ $(($successfulCommands | ForEach-Object { "- ``$($_.CommandName)`` `n" }) -join
     }
 
     Write-Host '::group::Build docs - Move markdown files from public functions folder to docs output folder'
-    Get-ChildItem -Path $PublicFunctionsFolder -Recurse -Force -Include '*.md' | ForEach-Object {
-        $file = $_
+    # Enumerate the public markdown once and reuse it (no second tree walk).
+    $publicMarkdownFiles = @(Get-ChildItem -Path $PublicFunctionsFolder -Recurse -Force -File -Include '*.md')
+
+    # Folders that provide an explicit index page. Detected case-insensitively because the runner
+    # filesystem is case-sensitive. Two index pages that differ only by case (index.md and
+    # Index.md) are ambiguous, so fail fast instead of silently overwriting one.
+    $explicitIndexFolders = [System.Collections.Generic.HashSet[string]]::new()
+    $indexGroups = $publicMarkdownFiles | Where-Object { $_.Name -ieq 'index.md' } | Group-Object { $_.Directory.FullName }
+    foreach ($group in $indexGroups) {
+        if ($group.Count -gt 1) {
+            $names = ($group.Group.Name | Sort-Object) -join ', '
+            throw "Ambiguous section index in '$($group.Name)': multiple index pages ($names). Keep only one index.md."
+        }
+        [void]$explicitIndexFolders.Add($group.Name)
+    }
+
+    foreach ($file in $publicMarkdownFiles) {
         $relPath = [System.IO.Path]::GetRelativePath($PublicFunctionsFolder.FullName, $file.FullName)
         Write-Host " - $relPath"
         Write-Host "   Path:     $file"
 
         $docsFilePath = ($file.FullName).Replace($PublicFunctionsFolder.FullName, $docsOutputFolder)
+
+        # A group's overview page becomes the section landing page (index.md) so the navigation
+        # shows it when the group is selected, instead of a page nested under the group. Authors
+        # can either name it after the folder (e.g. Auth/Auth.md) or provide Auth/index.md directly.
+        $parentFolder = Split-Path -Path $file.FullName -Parent
+        $parentFolderName = Split-Path -Path $parentFolder -Leaf
+        if ($file.Name -ieq 'index.md') {
+            # Normalize any casing (Index.md/INDEX.md) to index.md so it is treated as the
+            # section index on case-sensitive filesystems.
+            $docsFilePath = Join-Path -Path (Split-Path -Path $docsFilePath -Parent) -ChildPath 'index.md'
+            Write-Host '   Section index page detected - publishing as index.md'
+        } elseif ($file.BaseName -eq $parentFolderName) {
+            if ($explicitIndexFolders.Contains($parentFolder)) {
+                Write-Warning "Ignoring group overview '$relPath' as the section index; folder already has an explicit index.md."
+            } else {
+                $docsFilePath = Join-Path -Path (Split-Path -Path $docsFilePath -Parent) -ChildPath 'index.md'
+                Write-Host '   Group overview page detected - publishing as section index (index.md)'
+            }
+        }
+
         Write-Host "   MD path:  $docsFilePath"
         $docsFolderPath = Split-Path -Path $docsFilePath -Parent
         $null = New-Item -Path $docsFolderPath -ItemType Directory -Force
diff --git a/tests/srcTestRepo/src/functions/public/SomethingElse/SomethingElse.md b/tests/srcTestRepo/src/functions/public/SomethingElse/index.md
similarity index 100%
rename from tests/srcTestRepo/src/functions/public/SomethingElse/SomethingElse.md
rename to tests/srcTestRepo/src/functions/public/SomethingElse/index.md
diff --git a/tests/srcTestRepo/src/functions/public/Widgets/Index.md b/tests/srcTestRepo/src/functions/public/Widgets/Index.md
new file mode 100644
index 0000000..f3eaf5b
--- /dev/null
+++ b/tests/srcTestRepo/src/functions/public/Widgets/Index.md
@@ -0,0 +1,4 @@
+# Widgets
+
+This is the section overview for the Widgets group, authored as `Index.md` to verify
+case-insensitive detection and normalization to `index.md`.