diff --git a/autoprep/preprocessor.py b/autoprep/preprocessor.py
new file mode 100644
index 0000000..0cb3337
--- /dev/null
+++ b/autoprep/preprocessor.py
@@ -0,0 +1,63 @@
+from scipy import stats
+import pandas as pd
+
+
+class Preprocessor:
+    def __init__(self, series: pd.Series):
+        print(series.dtype.name)
+        if series.dtype.name == 'int64':
+            self.prep = NumPreprocessor()
+        elif series.dtype.name == 'float64':
+            self.prep = NumPreprocessor()
+        elif series.dtype.name == 'bool':
+            self.prep = BoolPreprocessor()
+        elif series.dtype.name == 'datetime64':
+            self.prep = DatePreprocessor()
+        else:
+            self.prep = CatPreprocessor()
+        self.series = series
+
+    def apply(self):
+        return self.prep.apply(self.series)
+
+
+class NumPreprocessor:
+    @staticmethod
+    def _fill(series: pd.Series):
+        return series.fillna(series.median())
+
+    @staticmethod
+    def _normarize(series: pd.Series):
+        return pd.Series(stats.zscore(series))
+
+    def apply(self, series: pd.Series):
+        return self._normarize(self._fill(series))
+
+
+class BoolPreprocessor:
+    @staticmethod
+    def _fill(series):
+        pass
+
+    def apply(self, series):
+        pass
+
+
+class DatePreprocessor:
+    @staticmethod
+    def _fill(series):
+        pass
+
+    def apply(self, series):
+        pass
+
+
+class CatPreprocessor:
+    def _fill(self):
+        pass
+
+    def _encoding(self):
+        pass
+
+    def apply(self, series):
+        pass
diff --git a/setup.py b/setup.py
index 5888828..0c8a467 100644
--- a/setup.py
+++ b/setup.py
@@ -18,6 +18,6 @@ def read(filename):
     packages=['autoprep'],
     long_description=read('README.md'),
     long_description_content_type="text/markdown",
-    install_requires=['numpy', 'pandas'],
+    install_requires=['numpy', 'scipy', 'pandas'],
     classifiers=[]
 )
diff --git a/tests/test_preprocessor.py b/tests/test_preprocessor.py
new file mode 100644
index 0000000..1f348b7
--- /dev/null
+++ b/tests/test_preprocessor.py
@@ -0,0 +1,18 @@
+import unittest
+import pandas as pd
+from autoprep.preprocessor import Preprocessor
+
+
+class TestPreprocessor(unittest.TestCase):
+
+    def test_num_preprocessor(self):
+        series = pd.Series([18, 18, 20, None, 20, 22, 22, 30])
+        p = Preprocessor(series)
+        res = p.apply()
+        self.assertEqual(list(res),
+              [-0.9035624609139906, -0.9035624609139906, -0.34752402342845795, -0.34752402342845795,
+               -0.34752402342845795, 0.20851441405707474, 0.20851441405707474, 2.4326681639992054])
+
+
+if __name__ == '__main__':
+    unittest.main()