diff --git a/cssom-view-1/Overview.bs b/cssom-view-1/Overview.bs
index 8d8e3cb3774..eea210fb766 100644
--- a/cssom-view-1/Overview.bs
+++ b/cssom-view-1/Overview.bs
@@ -1997,6 +1997,18 @@ Issue: In what order are scrollend events dispatched? Ordered based on scroll st
     1. Otherwise, <a>fire an event</a> named <a event>scrollend</a> at <var>target</var>.
 1. Empty <var>doc</var>'s <a>pending scrollend event targets</a>.
 
+<h3 id=moving-viewports>Moving viewports</h3>
+
+This section integrates with the <a for=/>event loop</a> defined in HTML. [[!HTML]]
+
+When asked to <dfn export for=Document>run the move steps</dfn> for a {{Document}} <var>doc</var>, run these steps:
+
+1. If <var>doc</var>'s client window has had its position relative to the <a>Web-exposed screen area</a> changed
+    (e.g. as a result of the user moving the browser window)
+    since the last time these steps were run,
+    <a>fire an event</a> named <a event>move</a>
+    at the {{Window}} object associated with <var>doc</var>.
+
 <h3 id=event-summary>Event summary</h3>
 
 <i>This section is non-normative.</i>
@@ -2027,6 +2039,12 @@ Issue: In what order are scrollend events dispatched? Ordered based on scroll st
    <td>Fired at the {{VisualViewport}}, {{Document}}, or element when a scroll is <a lt="scroll completed">completed</a>: the
       {{VisualViewport}}, <a>viewport</a>, or element has been scrolled, the scroll sequence has ended and any scroll offset changes have
       been applied.
+  <tr>
+   <td><dfn event for="Window">move</dfn>
+   <td>{{Event}}
+   <td>{{Window}}
+   <td>Fired at the {{Window}} when the client window is moved relative to the <a>Web-exposed screen area</a>.
+  <tr>
 </table>