diff --git a/source/nix-language/attribute-sets.adoc b/source/nix-language/attribute-sets.adoc
index 30a22d2..d7801b4 100644
--- a/source/nix-language/attribute-sets.adoc
+++ b/source/nix-language/attribute-sets.adoc
@@ -32,6 +32,7 @@ false
 
 We can use the `//` operator to modify an attribute set.
 Recall that Nix values are immutable, so the result is a new value (the original is not modified).
+Attributes in the right-hand set take preference.
 
 [source]
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