diff --git a/xml/System.Text/SpanRuneEnumerator.xml b/xml/System.Text/SpanRuneEnumerator.xml
index 5a807ec8c1a..d76da978f47 100644
--- a/xml/System.Text/SpanRuneEnumerator.xml
+++ b/xml/System.Text/SpanRuneEnumerator.xml
@@ -19,8 +19,18 @@
     </Attribute>
   </Attributes>
   <Docs>
-    <summary>To be added.</summary>
-    <remarks>To be added.</remarks>
+    <summary>Provides an enumerator for the <see cref="T:System.Text.Rune" /> values represented by a span containing UTF-16 text.</summary>
+    <remarks>
+      <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This type is not intended to be referenced directly by application code. Instead, use the <xref:System.MemoryExtensions.EnumerateRunes%2A> method along with language-specific enumeration constructs to enumerate <xref:System.Text.Rune> values within spans.
+
+The `foreach` statement of the C# language (`for each` in C++, `For Each` in Visual Basic) hides the complexity of enumerators. Therefore, using `foreach` is recommended, instead of directly manipulating the enumerator.
+ 
+      ]]></format>
+    </remarks>
   </Docs>
   <Members>
     <Member MemberName="Current">
@@ -39,9 +49,8 @@
         <ReturnType>System.Text.Rune</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>Gets the <see cref="T:System.Text.Rune" /> at the current position of the enumerator.</summary>
+        <value>The <see cref="T:System.Text.Rune" /> at the current position of the enumerator.</value>
       </Docs>
     </Member>
     <Member MemberName="GetEnumerator">
@@ -61,9 +70,8 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Returns the current enumerator instance.</summary>
+        <returns>The current enumerator instance.</returns>
       </Docs>
     </Member>
     <Member MemberName="MoveNext">
@@ -83,10 +91,9 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Advances the enumerator to the next <see cref="T:System.Text.Rune" /> of the span.</summary>
+        <returns><see langword="true" /> if the enumerator successfully advanced to the next item; <see langword="false" /> if the end of the span has been reached.</returns>
       </Docs>
     </Member>
   </Members>
-</Type>
\ No newline at end of file
+</Type>
diff --git a/xml/System.Text/StringRuneEnumerator.xml b/xml/System.Text/StringRuneEnumerator.xml
index 6f673b59ab5..d18c0395440 100644
--- a/xml/System.Text/StringRuneEnumerator.xml
+++ b/xml/System.Text/StringRuneEnumerator.xml
@@ -30,8 +30,18 @@
     </Interface>
   </Interfaces>
   <Docs>
-    <summary>To be added.</summary>
-    <remarks>To be added.</remarks>
+    <summary>Provides an enumerator for the <see cref="T:System.Text.Rune" /> values represented by a string.</summary>
+    <remarks>
+      <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This type is not intended to be referenced directly by application code. Instead, use the <xref:System.String.EnumerateRunes> method along with language-specific enumeration constructs to enumerate <xref:System.Text.Rune> values within strings.
+
+The `foreach` statement of the C# language (`for each` in C++, `For Each` in Visual Basic) hides the complexity of enumerators. Therefore, using `foreach` is recommended, instead of directly manipulating the enumerator.
+ 
+      ]]></format>
+    </remarks>
   </Docs>
   <Members>
     <Member MemberName="Current">
@@ -53,9 +63,8 @@
         <ReturnType>System.Text.Rune</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>Gets the <see cref="T:System.Text.Rune" /> at the current position of the enumerator.</summary>
+        <value>The <see cref="T:System.Text.Rune" /> at the current position of the enumerator.</value>
       </Docs>
     </Member>
     <Member MemberName="GetEnumerator">
@@ -75,9 +84,8 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Returns the current enumerator instance.</summary>
+        <returns>The current enumerator instance.</returns>
       </Docs>
     </Member>
     <Member MemberName="MoveNext">
@@ -100,9 +108,8 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Advances the enumerator to the next <see cref="T:System.Text.Rune" /> of the string.</summary>
+        <returns><see langword="true" /> if the enumerator successfully advanced to the next item; <see langword="false" /> if the end of the string has been reached.</returns>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IEnumerable&lt;System.Text.Rune&gt;.GetEnumerator">
@@ -124,9 +131,18 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Returns the current enumerator instance.</summary>
+        <returns>The current enumerator instance.</returns>
+        <remarks>
+          <format type="text/markdown"><![CDATA[  
+  
+## Remarks  
+
+This member is an explicit interface member implementation. 
+It can be used only when the <xref:System.Text.StringRuneEnumerator> instance is cast to an <xref:System.Collections.Generic.IEnumerable%601> interface.  
+  
+ ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -148,9 +164,18 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Returns the current enumerator instance.</summary>
+        <returns>The current enumerator instance.</returns>
+        <remarks>
+          <format type="text/markdown"><![CDATA[  
+  
+## Remarks  
+
+This member is an explicit interface member implementation. 
+It can be used only when the <xref:System.Text.StringRuneEnumerator> instance is cast to an <xref:System.Collections.IEnumerable> interface.
+  
+ ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerator.Current">
@@ -172,9 +197,18 @@
         <ReturnType>System.Object</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>Gets the <see cref="T:System.Text.Rune" /> at the current position of the enumerator.</summary>
+        <value>The <see cref="T:System.Text.Rune" /> at the current position of the enumerator.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[  
+  
+## Remarks  
+
+This member is an explicit interface member implementation. 
+It can be used only when the <xref:System.Text.StringRuneEnumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+  
+ ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerator.Reset">
@@ -196,8 +230,17 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <remarks>To be added.</remarks>
+        <summary>Resets the current <see cref="T:System.Text.StringRuneEnumerator" /> instance to the beginning of the string.</summary>
+        <remarks>
+          <format type="text/markdown"><![CDATA[  
+  
+## Remarks  
+
+This member is an explicit interface member implementation. 
+It can be used only when the <xref:System.Text.StringRuneEnumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+  
+ ]]></format>
+        </remarks>        
       </Docs>
     </Member>
     <Member MemberName="System.IDisposable.Dispose">
@@ -219,9 +262,9 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <remarks>To be added.</remarks>
+        <summary>Releases all resources used by the current <see cref="T:System.Text.StringRuneEnumerator" /> instance.</summary>
+        <remarks>This method performs no operation and produces no side effects.</remarks>
       </Docs>
     </Member>
   </Members>
-</Type>
\ No newline at end of file
+</Type>