diff --git a/mu_map/dataset/transform.py b/mu_map/dataset/transform.py
index c27aaa57dfa7734a3bbf4b59a9d17b2a5b44c6c9..7b2685e0cebd568b611c4ac4bf22f69304906b33 100644
--- a/mu_map/dataset/transform.py
+++ b/mu_map/dataset/transform.py
@@ -5,13 +5,26 @@ from torch import Tensor
 
 
 class Transform:
+    """
+    Interface of a transformer. A transformer can be initialized and then applied to
+    an input tensor and expected output tensor as returned by a dataset. It can be
+    used for normalization and data augmentation.
+    """
+
     def __call__(
         self, inputs: Tensor, outputs_expected: Tensor
     ) -> Tuple[Tensor, Tensor]:
+        """
+        Apply the transformer to a pair of inputs and expected outputs in a dataset.
+        """
         return inputs, outputs_expected
 
 
 class SequenceTransform(Transform):
+    """
+    A transformer that applies a sequence of transformers sequentially.
+    """
+
     def __init__(self, transforms: List[Transform]):
         self.transforms = transforms