diff --git a/lib/active_model/serializer/adapter.rb b/lib/active_model/serializer/adapter.rb
index cba33619..87da1223 100644
--- a/lib/active_model/serializer/adapter.rb
+++ b/lib/active_model/serializer/adapter.rb
@@ -2,7 +2,7 @@ module ActiveModel
   class Serializer
     class Adapter
       extend ActiveSupport::Autoload
-      autoload :SimpleAdapter
+      autoload :JsonAdapter
       autoload :NullAdapter
       autoload :JsonApiAdapter
 
diff --git a/lib/active_model/serializer/adapter/simple_adapter.rb b/lib/active_model/serializer/adapter/json_adapter.rb
similarity index 87%
rename from lib/active_model/serializer/adapter/simple_adapter.rb
rename to lib/active_model/serializer/adapter/json_adapter.rb
index ebc22a87..8aba1c69 100644
--- a/lib/active_model/serializer/adapter/simple_adapter.rb
+++ b/lib/active_model/serializer/adapter/json_adapter.rb
@@ -1,7 +1,7 @@
 module ActiveModel
   class Serializer
     class Adapter
-      class SimpleAdapter < Adapter
+      class JsonAdapter < Adapter
         def serializable_hash(options = {})
           serializer.attributes.each_with_object({}) do |(attr, value), h|
             h[attr] = value
diff --git a/lib/active_model/serializer/configuration.rb b/lib/active_model/serializer/configuration.rb
index 87ed16ab..ef57262c 100644
--- a/lib/active_model/serializer/configuration.rb
+++ b/lib/active_model/serializer/configuration.rb
@@ -6,7 +6,7 @@ module ActiveModel
 
       included do |base|
         base.config.array_serializer = ActiveModel::Serializer::ArraySerializer
-        base.config.adapter = :simple
+        base.config.adapter = :json
       end
     end
   end
diff --git a/lib/active_model_serializers.rb b/lib/active_model_serializers.rb
index 894ca869..c96b90a9 100644
--- a/lib/active_model_serializers.rb
+++ b/lib/active_model_serializers.rb
@@ -1,7 +1,6 @@
 require "active_model"
 require "active_model/serializer/version"
 require "active_model/serializer"
-require "active_model/serializer/adapter/simple_adapter"
 
 begin
   require 'action_controller'
diff --git a/test/adapter/simple_adapter_test.rb b/test/adapter/json_adapter_test.rb
similarity index 85%
rename from test/adapter/simple_adapter_test.rb
rename to test/adapter/json_adapter_test.rb
index 5805184f..b4dfa373 100644
--- a/test/adapter/simple_adapter_test.rb
+++ b/test/adapter/json_adapter_test.rb
@@ -3,12 +3,12 @@ require 'test_helper'
 module ActiveModel
   class Serializer
     class Adapter
-      class SimpleAdapterTest < Minitest::Test
+      class JsonAdapterTest < Minitest::Test
         def setup
           @profile = Profile.new({ name: 'Name 1', description: 'Description 1', comments: 'Comments 1' })
           @profile_serializer = ProfileSerializer.new(@profile)
 
-          @adapter = SimpleAdapter.new(@profile_serializer)
+          @adapter = JsonAdapter.new(@profile_serializer)
         end
 
         def test_serializable_hash
diff --git a/test/serializers/adapter_for_test.rb b/test/serializers/adapter_for_test.rb
index 668dd6b0..651e511a 100644
--- a/test/serializers/adapter_for_test.rb
+++ b/test/serializers/adapter_for_test.rb
@@ -11,7 +11,7 @@ module ActiveModel
 
       def test_returns_default_adapter
         adapter = ActiveModel::Serializer.adapter
-        assert_equal ActiveModel::Serializer::Adapter::SimpleAdapter, adapter
+        assert_equal ActiveModel::Serializer::Adapter::JsonAdapter, adapter
       end
 
       def test_overwrite_adapter_with_symbol
diff --git a/test/serializers/configuration_test.rb b/test/serializers/configuration_test.rb
index 43837269..eec00436 100644
--- a/test/serializers/configuration_test.rb
+++ b/test/serializers/configuration_test.rb
@@ -8,7 +8,7 @@ module ActiveModel
       end
 
       def test_adapter
-        assert_equal :simple, ActiveModel::Serializer.config.adapter
+        assert_equal :json, ActiveModel::Serializer.config.adapter
       end
     end
   end