diff --git a/browser/common.py b/browser/common.py
index 8407f8f..762fba1 100644
--- a/browser/common.py
+++ b/browser/common.py
@@ -422,6 +422,8 @@ class BaseView(GenericView, I18NView):
     def renderDescription(self, text=None):
         if text is None:
             text = self.description
+        if text is None:
+            return u''
         htmlPattern = re.compile(r'<(.+)>.+</\1>')
         if htmlPattern.search(text):
             return text
diff --git a/browser/concept.py b/browser/concept.py
index e38fb1c..1091ec1 100644
--- a/browser/concept.py
+++ b/browser/concept.py
@@ -368,7 +368,7 @@ class ConceptView(BaseView):
 
     def parents(self):
         rels = sorted(self.context.getParentRelations(),
-                      key=(lambda x: x.first.title.lower()))
+                      key=(lambda x: x.first.title and x.first.title.lower()))
         for r in rels:
             yield self.childViewFactory(r, self.request)
 
diff --git a/concept.py b/concept.py
index 9a27490..14367ea 100644
--- a/concept.py
+++ b/concept.py
@@ -201,7 +201,7 @@ class Concept(Contained, Persistent):
         relationships = [ConceptRelation(None, self, p) for p in predicates]
         if sort == 'default':
             #sort = lambda x: (x.order, x.first.title.lower())
-            sort = lambda x: (x.first.title.lower())
+            sort = lambda x: (x.first.title and x.first.title.lower())
         rels = (r for r in getRelations(parent, self, relationships=relationships)
                   if canListObject(r.first, noSecurityCheck))
         return sorted(rels, key=sort)
diff --git a/expert/browser/search.py b/expert/browser/search.py
index f368042..5a08a2f 100644
--- a/expert/browser/search.py
+++ b/expert/browser/search.py
@@ -249,7 +249,7 @@ class Search(BaseView):
         result = [r for r in result if self.checkStates(r)]
         fv = FilterView(self.context, self.request)
         result = fv.apply(result)
-        result = sorted(result, key=lambda x: x.title.lower())
+        result = sorted(result, key=lambda x: x.title and x.title.lower())
         return self.viewIterator(result)
 
     def checkStates(self, obj):