diff --git a/README.md b/README.md
index 24281d9..a8a68cc 100644
--- a/README.md
+++ b/README.md
@@ -203,6 +203,13 @@ void notThrowing()
 should(&notThrowing).not.Throw;
 ```
 
+## An example of failing an assertion
+
+<img src="https://zardoz89.github.io/pijamas/assets/img/error.png" />
+
+A failing assertation throws an Exception with information of what was
+expected, and file and line number where it failed
+
 ## Need more documentation?
 
 I know the documentation is still somewhat lacking, but it's better than
diff --git a/docs/assets/img/error.png b/docs/assets/img/error.png
new file mode 100644
index 0000000..4fd0ce2
Binary files /dev/null and b/docs/assets/img/error.png differ