diff --git a/src/pyreqif/create.py b/src/pyreqif/create.py
index b2ff05f..f19d4f5 100644
--- a/src/pyreqif/create.py
+++ b/src/pyreqif/create.py
@@ -13,11 +13,11 @@ def createDocument(id, title="title", comment="created by pyreqif"):
 def addDocType(id, mydoc, lastChange=datetime.datetime.today().isoformat(), longName = "doc_type"):
     mydoc.specificationTypes.add({"identifier": id, "lastChange": lastChange, "longName": longName})
 
-def addDatatype(id, mydoc, type="document", lastChange=datetime.datetime.today().isoformat(), longName="xhtml", values = None):
+def addDatatype(id, mydoc, type="document", lastChange=datetime.datetime.today().isoformat(), longName="xhtml", values = None, multiValued=False):
     if values is None:
         mydoc.addDatatype({"identifier":id, "type":type, "lastChange": lastChange, "longName":longName})
     else:
-        mydoc.addDatatype({"identifier":id, "type":type, "lastChange": lastChange, "longName":longName, "values" : values})
+        mydoc.addDatatype({"identifier":id, "type":type, "lastChange": lastChange, "longName":longName, "values" : values, "multiValued" : multiValued})
 
 
 def addSpecRelationType(id, mydoc, longName, lastChange=datetime.datetime.today().isoformat()):
diff --git a/src/pyreqif/reqif.py b/src/pyreqif/reqif.py
index b7f5eca..58de112 100644
--- a/src/pyreqif/reqif.py
+++ b/src/pyreqif/reqif.py
@@ -143,7 +143,10 @@ def dump(doc, f):
                 attribDict = py2reqif(ref.toDict())
                 if "TYPE" in attribDict and attribDict["TYPE"] == "enum":
                     attribDict.pop("TYPE")
-                    attribDict["MULTI-VALUED"] = "false"
+                    if attribDict["multiValued"]:
+                        attribDict["MULTI-VALUED"] = "true"
+                    else:
+                        attribDict["MULTI-VALUED"] = "false"
                     enumXml = createSubElement(attributesXml,"ATTRIBUTE-DEFINITION-ENUMERATION", attributes=attribDict)
 #                    for value,label in attribDict.iteritems():
                     for value, label in attribDict.items():
diff --git a/src/pyreqif/rif.py b/src/pyreqif/rif.py
index 1d5f306..1675f7d 100644
--- a/src/pyreqif/rif.py
+++ b/src/pyreqif/rif.py
@@ -500,7 +500,10 @@ def dump(doc, f):
                 attribDict = py2reqif(ref.toDict())
                 if "TYPE" in attribDict and attribDict["TYPE"] == "enum":
                     attribDict.pop("TYPE")
-                    attribDict["MULTI-VALUED"] = "false"
+                    if attribDict["multiValued"]:
+                        attribDict["MULTI-VALUED"] = "true"
+                    else:
+                        attribDict["MULTI-VALUED"] = "false"
                     enumXml = createSubElement(attributesXml,"ATTRIBUTE-DEFINITION-ENUMERATION", attributes=attribDict)
                     for value,label in attribDict.items():
                         if value == "typeRef":