diff --git a/README.md b/README.md
index ad26a6ce..90a8714d 100644
--- a/README.md
+++ b/README.md
@@ -40,7 +40,7 @@ other the common Ruby JSON parsers. So far is has achieved that at about 2
 time faster than Yajl for parsing and 3 or more times faster writing JSON.
 
 Oj has several dump or serialization modes which control how Objects are
-converted to JSON. These modes are set with the :effort option in either the
+converted to JSON. These modes are set with the :mode option in either the
 default options or as one of the options to the dump() method.
 
 - :strict mode will only allow the 7 basic JSON types to be serialized. Any other Object
diff --git a/lib/oj.rb b/lib/oj.rb
index c112a2e4..9a5df445 100644
--- a/lib/oj.rb
+++ b/lib/oj.rb
@@ -2,7 +2,7 @@
 # optimized JSON handling.
 # 
 # Oj has several dump or serialization modes which control how Objects are
-# converted to JSON. These modes are set with the :effort option in either the
+# converted to JSON. These modes are set with the :mode option in either the
 # default options or as one of the options to the dump() method.
 # 
 # - :strict mode will only allow the 7 basic JSON types to be serialized. Any other Object