diff --git a/pym/cl_datavars.py b/pym/cl_datavars.py
index 11a13b5..cdf7173 100644
--- a/pym/cl_datavars.py
+++ b/pym/cl_datavars.py
@@ -854,7 +854,7 @@ class _varsXML:
         """Add var to XML"""
         dictVar = {"indent":self.indent,
                    "name":name,
-                   "value":str(value)}
+                   "value":self.serialize(value)}
         self.varsXML += self.templateVar %dictVar
 
     def addList(self, name, valueList):
@@ -864,7 +864,7 @@ class _varsXML:
         varXml = self.templateListStart %dictVar
         for value in valueList:
             dictValue = {"indent":self.indent,
-                         "value":str(value)}
+                         "value":self.serialize(value)}
             varXml += self.templateListValue %dictValue
         varXml += self.templateListEnd %dictVar
         self.varsXML += varXml
@@ -877,11 +877,16 @@ class _varsXML:
         for nameDict, valueDict in valueDict.items():
             dictValue = {"indent":self.indent,
                          "name":nameDict,
-                         "value":str(valueDict)}
+                         "value":self.serialize(valueDict)}
             varXml += self.templateDictValue %dictValue
         varXml += self.templateDictEnd %dictVar
         self.varsXML += varXml
 
+    def serialize(self, value):
+        """Serialization"""
+        return str(value).replace("&","&amp;").replace("<","&lt;").replace(">",
+                                  "&gt;")
+
     def toXML(self):
         dictXML = {"declaration":self.declaration,
                    "rootStart":self.rootElementStart,