diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1de0b62..4a6430a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,7 +7,7 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Added
 
-- Nothing.
+- [#16](https://github.com/elie29/validator/issues/16) Do not append none existing item.
 
 ### Changed
 
diff --git a/README.md b/README.md
index 4dbda00..7a9f5b2 100644
--- a/README.md
+++ b/README.md
@@ -121,6 +121,14 @@ class MyValueRule extends AbstractRule
 }
 ```
 
+## Validated Context
+
+Once validate is called, we can use validatedContext method in order to retrieve all validated values from the original
+context.
+
+By default, all keys set in the rules array will be found in the validatedContext array. However, if we don't want to append
+non existing keys, we should call appendExistingItemsOnly(true) before validation.
+
 ## Assertion Integration
 
 Instead of using assertion key by key, you can validate the whole context and than use [Assertion](https://github.com/beberlei/assert) or [Assert](https://github.com/webmozart/assert) as follow: