diff --git a/behat.yml b/behat.yml
index 0cc5f068..f772c879 100644
--- a/behat.yml
+++ b/behat.yml
@@ -11,9 +11,10 @@ default:
         - SilverStripe\BehatExtension\Context\EmailContext
         - SilverStripe\CMS\Tests\Behaviour\LoginContext
         - SilverStripe\CMS\Tests\Behaviour\ThemeContext
-        - SilverStripe\CMS\Tests\Behaviour\FixtureContext:
+        # Using asset-admin for fixture context to get iAttachTheFileToDropzone()
+        - SilverStripe\AssetAdmin\Tests\Behat\Context\FixtureContext:
             # Note: double indent for args is intentional
-            - '%paths.modules.subsites%/tests/behat/features/files/'
+            - '%paths.modules.subsites%/tests/behat/files/'
 
   extensions:
     SilverStripe\BehatExtension\MinkExtension:
diff --git a/tests/behat/features/operate-subsites.feature b/tests/behat/features/operate-subsites.feature
new file mode 100644
index 00000000..dd2eaf5b
--- /dev/null
+++ b/tests/behat/features/operate-subsites.feature
@@ -0,0 +1,82 @@
+@javascript
+Feature: Create and select a subsite
+  As a CMS user
+  I want to be able to select a subsite
+  So that I can edit content for a specific subsite
+
+  Background:
+    # There's a bug where you need CMS_ACCESS_CMSMain rather than CMS_ACCESS_LeftAndMain permissions to
+    # use subsites as expected
+    # Given the "group" "EDITOR group" has permissions "CMS_ACCESS_LeftAndMain" and "FILE_EDIT_ALL"
+    Given the "group" "EDITOR group" has permissions "CMS_ACCESS_CMSMain" and "CMS_ACCESS_AssetAdmin" and "FILE_EDIT_ALL"
+    And a "page" "My page" with "URLSegment"="my-page", "Content"="My page content"
+    And an "image" "file1.jpg"
+    And an "image" "file2.jpg"
+
+  Scenario: I can operate subsites
+
+    # Create subsite as Admin
+    Given I am logged in with "ADMIN" permissions
+    Then I go to "admin/subsites"
+
+    # Add subsites button is not a regular button, so click using css selector
+    And I click on the ".btn-toolbar .btn__title" element
+    And I fill in "Subsite Name" with "My subsite"
+    And I press "Create"
+
+    # Add a file to the main site
+    When I go to "admin/assets"
+    And I press the "Add folder" button
+    And I select "Main site" from "SubsitesSelect"
+    # Using a short folder name so that it doesn't get truncated on the frontend
+    And I fill in "Folder name" with "mfol"
+    And I press the "Create" button
+    When I go to "admin/assets"
+
+    And I click on the file named "mfol" in the gallery
+    And I attach the file "file1.jpg" to dropzone "gallery-container"
+
+    # Change to Editor user
+    When I go to "/Security/login"
+    And I press the "Log in as someone else" button
+    When I am logged in with "EDITOR" permissions
+    And I go to "admin/pages"
+
+    # Can see main site page on main site
+    When I go to "admin/pages"
+    Then I should see "My page" in the tree
+
+    # Cannot see main site page on subsite
+    When I select "My subsite" from "SubsitesSelect"
+    And I go to "admin/pages"
+    Then I should not see "My page" in the tree
+
+    # Create a page on the subsite
+    When I press the "Add new" button
+    And I select the "Page" radio button
+    And I press the "Create" button
+    When I fill in "Page name" with "My subsite page"
+    And I press the "Publish" button
+    Then I should see "My subsite page"
+
+    # Can see main site folders/files from subsite
+    When I go to "admin/assets"
+    Then I should see "mfol"
+    When I click on the file named "mfol" in the gallery
+    Then I should see "file1"
+
+    # Add a file to the subsite
+    When I go to "admin/assets"
+    And I select "My subsite" from "SubsitesSelect"
+    And I press the "Add folder" button
+    And I fill in "Folder name" with "sfol"
+    And I press the "Create" button
+    When I go to "admin/assets"
+    And I click on the file named "sfol" in the gallery
+    And I attach the file "file2.jpg" to dropzone "gallery-container"
+
+    # Change back to main subsite - cannot see subsite folders/files
+    When I go to "admin/assets"
+    And I select "Main site" from "SubsitesSelect"
+    Then I should see "mfol"
+    Then I should not see "My subsite page"
diff --git a/tests/behat/features/preview-navigation.feature b/tests/behat/features/preview-navigation.feature
index 81492ac1..fa2c2a86 100644
--- a/tests/behat/features/preview-navigation.feature
+++ b/tests/behat/features/preview-navigation.feature
@@ -4,18 +4,19 @@ Feature: Preview navigation
   In order to preview my content
 
   Background:
-    Given a "subsite" "My subsite"
-    And a "page" "My page" with "URLSegment"="my-page", "Content"="My page content <a name='aname'>aname</a><a href='other-page'>ahref</a>" and "Subsite"="=>SilverStripe\Subsites\Model\Subsite.My subsite"
-    And a "page" "Other page" with "URLSegment"="other-page", "Content"="Other page content <a href='my-page'>Goto my page></a>" and "Subsite"="=>SilverStripe\Subsites\Model\Subsite.My subsite"
-    Given a "member" "Joe" belonging to "Admin Group" with "Email"="joe@test.com" and "Password"="Password1"
-    And the "group" "Admin Group" has permissions "Full administrative rights"
-    And I log in with "joe@test.com" and "Password1"
+    Given a "subsite" "MySubsite"
+    And a "page" "My page" with "URLSegment"="my-page", "Content"="My page content <a name='aname'>aname</a> <a href='[sitetree_link,id=5]'>ahref</a>" and "SubsiteID"="1"
+    And a "page" "Other page" with "URLSegment"="other-page", "Content"="Other page content <a href='[sitetree_link,id=4]'>Goto my page</a>" and "SubsiteID"="1"
 
   @javascript
   Scenario: I can navigate the subsite preview
-    When I go to "admin"
-    And I select "My subsite" from "SubsitesSelect"
-    And I go to "admin/pages"
+    Given I am logged in with "ADMIN" permissions
+    When I go to "/admin/pages"
+    And I select "MySubsite" from "SubsitesSelect"
+    And I click on "My page" in the tree
+    And I press the "Publish" button
+    And I click on "Other page" in the tree
+    And I press the "Publish" button
     And I click on "My page" in the tree
     And I set the CMS mode to "Preview mode"
     And I follow "ahref" in preview
diff --git a/tests/behat/features/select-a-subsite.feature b/tests/behat/features/select-a-subsite.feature
deleted file mode 100644
index 1b183d1b..00000000
--- a/tests/behat/features/select-a-subsite.feature
+++ /dev/null
@@ -1,21 +0,0 @@
-@javascript
-Feature: Select a subsite
-  As a CMS user
-  I want to be able to select a subsite
-  So that I can edit content for a specific subsite
-
-  Background:
-    Given a "subsite" "Subsite B"
-    And a "page" "My page" with "URLSegment"="my-page", "Content"="My page content"
-    And I am logged in with "ADMIN" permissions
-    Then I go to "admin/pages"
-
-  Scenario: Default site contains default pages
-    When I select "Main site" from "SubsitesSelect"
-    And I go to "admin/pages"
-    Then I should see "My page" in the tree
-
-  Scenario: I can switch to another subsite
-    When I select "Subsite B" from "SubsitesSelect"
-    And I go to "admin/pages"
-    Then I should not see "My page" in the tree
diff --git a/tests/behat/files/file1.jpg b/tests/behat/files/file1.jpg
new file mode 100644
index 00000000..beb5a91b
Binary files /dev/null and b/tests/behat/files/file1.jpg differ
diff --git a/tests/behat/files/file2.jpg b/tests/behat/files/file2.jpg
new file mode 100644
index 00000000..fc834a45
Binary files /dev/null and b/tests/behat/files/file2.jpg differ