diff --git a/docx-core/src/documents/elements/caps.rs b/docx-core/src/documents/elements/caps.rs
index 8da7ba2..cbdce33 100644
--- a/docx-core/src/documents/elements/caps.rs
+++ b/docx-core/src/documents/elements/caps.rs
@@ -1,5 +1,7 @@
 use serde::{Deserialize, Serialize, Serializer};
 
+use crate::{xml_builder::XMLBuilder, BuildXML};
+
 // use crate::documents::BuildXML;
 // use crate::xml_builder::*;
 
@@ -33,3 +35,10 @@ impl Serialize for Caps {
         serializer.serialize_bool(self.val)
     }
 }
+
+impl BuildXML for Caps {
+    fn build(&self) -> Vec<u8> {
+        let b = XMLBuilder::new();
+        b.caps(&self.val.to_string()).build()
+    }
+}
diff --git a/docx-core/src/documents/elements/run_property.rs b/docx-core/src/documents/elements/run_property.rs
index 7503787..cccc043 100644
--- a/docx-core/src/documents/elements/run_property.rs
+++ b/docx-core/src/documents/elements/run_property.rs
@@ -165,6 +165,7 @@ impl BuildXML for RunProperty {
             .add_optional_child(&self.color)
             .add_optional_child(&self.bold)
             .add_optional_child(&self.bold_cs)
+            .add_optional_child(&self.caps)
             .add_optional_child(&self.italic)
             .add_optional_child(&self.italic_cs)
             .add_optional_child(&self.strike)
diff --git a/docx-core/src/xml_builder/elements.rs b/docx-core/src/xml_builder/elements.rs
index 61911ac..83c586a 100644
--- a/docx-core/src/xml_builder/elements.rs
+++ b/docx-core/src/xml_builder/elements.rs
@@ -179,6 +179,8 @@ impl XMLBuilder {
     closed!(b, "w:b");
     closed!(b_cs, "w:bCs");
 
+    closed_with_str!(caps, "w:caps");
+
     closed!(i, "w:i");
     closed!(i_cs, "w:iCs");