diff --git a/brainles_preprocessing/normalization/__init__.py b/brainles_preprocessing/normalization/__init__.py
index e69de29..bf20950 100644
--- a/brainles_preprocessing/normalization/__init__.py
+++ b/brainles_preprocessing/normalization/__init__.py
@@ -0,0 +1,3 @@
+from .normalizer_base import Normalizer
+from .percentile_normalizer import PercentileNormalizer
+from .windowing_normalizer import WindowingNormalizer