diff --git a/pyFTS/nonstationary/__init__.py b/pyFTS/nonstationary/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/pyFTS/common/NonStationary.py b/pyFTS/nonstationary/common.py
similarity index 99%
rename from pyFTS/common/NonStationary.py
rename to pyFTS/nonstationary/common.py
index 8eccb43..6fafbfb 100644
--- a/pyFTS/common/NonStationary.py
+++ b/pyFTS/nonstationary/common.py
@@ -88,5 +88,5 @@ class NonStationaryFuzzySet(FuzzySet.FuzzySet):
         :param mf: NonStationary Membership Function
         """
         super(FuzzySet, self).__init__(name=name, mf=mf, parameters=None, centroid=None)
-        
+
 
diff --git a/pyFTS/common/Pertubation.py b/pyFTS/nonstationary/pertubation.py
similarity index 100%
rename from pyFTS/common/Pertubation.py
rename to pyFTS/nonstationary/pertubation.py