diff --git a/src/XML/wsa_200508/RelatesTo.php b/src/XML/wsa_200508/RelatesTo.php
index d3e04f8..d9c8deb 100644
--- a/src/XML/wsa_200508/RelatesTo.php
+++ b/src/XML/wsa_200508/RelatesTo.php
@@ -9,10 +9,9 @@
 use SimpleSAML\XML\Exception\InvalidDOMElementException;
 use SimpleSAML\XML\Exception\SchemaViolationException;
 use SimpleSAML\XML\ExtendableAttributesTrait;
+use SimpleSAML\XML\URIElementTrait;
 use SimpleSAML\XML\XsNamespace as NS;
 
-use function is_null;
-
 /**
  * Class representing a wsa:RelatesTo element.
  *
@@ -21,6 +20,7 @@
 final class RelatesTo extends AbstractWsaElement
 {
     use ExtendableAttributesTrait;
+    use URIElementTrait;
 
     /** The namespace-attribute for the xs:anyAttribute element */
     public const XS_ANY_ATTR_NAMESPACE = NS::OTHER;
@@ -29,15 +29,18 @@ final class RelatesTo extends AbstractWsaElement
     /**
      * Initialize a wsa:RelatesTo
      *
+     * @param string $content
      * @param string|null $RelationshipType
      * @param list<\SimpleSAML\XML\Attribute> $namespacedAttributes
      */
     public function __construct(
+        string $content,
         protected ?string $RelationshipType = 'http://www.w3.org/2005/08/addressing/reply',
         array $namespacedAttributes = [],
     ) {
         Assert::nullOrValidURI($RelationshipType, SchemaViolationException::class);
 
+        $this->setContent($content);
         $this->setAttributesNS($namespacedAttributes);
     }
 
@@ -53,17 +56,6 @@ public function getRelationshipType(): ?string
     }
 
 
-    /**
-     * Test if an object, at the state it's in, would produce an empty XML-element
-     *
-     * @return bool
-     */
-    public function isEmptyElement(): bool
-    {
-        return is_null($this->RelationshipType) && empty($this->namespacedAttributes);
-    }
-
-
     /*
      * Convert XML into an RelatesTo element
      *
@@ -79,6 +71,7 @@ public static function fromXML(DOMElement $xml): static
         Assert::same($xml->namespaceURI, RelatesTo::NS, InvalidDOMElementException::class);
 
         return new static(
+            $xml->textContent,
             self::getOptionalAttribute($xml, 'RelationshipType', null),
             self::getAttributesNSFromXML($xml),
         );
@@ -94,6 +87,7 @@ public static function fromXML(DOMElement $xml): static
     public function toXML(?DOMElement $parent = null): DOMElement
     {
         $e = $this->instantiateParentElement($parent);
+        $e->textContent = $this->getContent();
 
         if ($this->getRelationshipType() !== null) {
             $e->setAttribute('RelationshipType', $this->getRelationshipType());
diff --git a/tests/WSSecurity/XML/wsa_200508/RelatesToTest.php b/tests/WSSecurity/XML/wsa_200508/RelatesToTest.php
index e43c52e..059cbf5 100644
--- a/tests/WSSecurity/XML/wsa_200508/RelatesToTest.php
+++ b/tests/WSSecurity/XML/wsa_200508/RelatesToTest.php
@@ -50,25 +50,15 @@ public function testMarshalling(): void
     {
         $domAttr = new Attribute('urn:test:something', 'test', 'attr1', 'testval1');
 
-        $relatesTo = new RelatesTo('http://www.w3.org/2005/08/addressing/reply', [$domAttr]);
-        $this->assertFalse($relatesTo->isEmptyElement());
-
-        $this->assertEquals(
-            self::$xmlRepresentation->saveXML(self::$xmlRepresentation->documentElement),
-            strval($relatesTo),
+        $relatesTo = new RelatesTo(
+            'urn:x-simplesamlphp:namespace',
+            'http://www.w3.org/2005/08/addressing/reply',
+            [$domAttr],
         );
-    }
 
-
-    /**
-     */
-    public function testMarshallingWithNoContent(): void
-    {
-        $relatesTo = new RelatesTo(null, []);
         $this->assertEquals(
-            '<wsa10:RelatesTo xmlns:wsa10="http://www.w3.org/2005/08/addressing"/>',
+            self::$xmlRepresentation->saveXML(self::$xmlRepresentation->documentElement),
             strval($relatesTo),
         );
-        $this->assertTrue($relatesTo->isEmptyElement());
     }
 }
diff --git a/tests/resources/xml/wsa/200508/RelatesTo.xml b/tests/resources/xml/wsa/200508/RelatesTo.xml
index 19c57de..b25c54d 100644
--- a/tests/resources/xml/wsa/200508/RelatesTo.xml
+++ b/tests/resources/xml/wsa/200508/RelatesTo.xml
@@ -1 +1 @@
-<wsa10:RelatesTo xmlns:wsa10="http://www.w3.org/2005/08/addressing" RelationshipType="http://www.w3.org/2005/08/addressing/reply" xmlns:test="urn:test:something" test:attr1="testval1" />
+<wsa10:RelatesTo xmlns:wsa10="http://www.w3.org/2005/08/addressing" RelationshipType="http://www.w3.org/2005/08/addressing/reply" xmlns:test="urn:test:something" test:attr1="testval1">urn:x-simplesamlphp:namespace</wsa10:RelatesTo>