diff --git a/doc/examples/plot_rag_merge.py b/doc/examples/plot_rag_merge.py
index c310ed5a..22cae6da 100644
--- a/doc/examples/plot_rag_merge.py
+++ b/doc/examples/plot_rag_merge.py
@@ -1,3 +1,15 @@
+"""
+===========
+RAG Merging
+===========
+
+This example constructs a Region Adjacency Graph (RAG) and progressively merges
+regions which are similar in color. Merging two adjacent regions produces
+a new regions with all the pixels from the merged regions. Regions are merged
+till no two adjacent regions are similar enough.
+
+"""
+
 from skimage import graph, data, io, segmentation, color