diff --git a/README.md b/README.md
index 1782768d..f8c74150 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,7 @@ development.**
 
 # Installing Serializers
 
-The easiest way to install `ActiveModel::Serializers` is to add it to your 
+The easiest way to install `ActiveModel::Serializers` is to add it to your
 `Gemfile`:
 
 ```ruby
@@ -408,6 +408,8 @@ You may also use the `:serializer` option to specify a custom serializer class a
   has_one :reviewer, :polymorphic => true
 ```
 
+Serializers are only concerned with multiplicity, and not ownership. `belongs_to` ActiveRecord associations can be included using `has_one` in your serializer.
+
 ## Embedding Associations
 
 By default, associations will be embedded inside the serialized object. So if