diff --git a/railties/CHANGELOG b/railties/CHANGELOG
index c624a1b41a..39b61a186e 100644
--- a/railties/CHANGELOG
+++ b/railties/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Support multiple config.after_initialize blocks so plugins and apps can more easily cooperate.  #9582 [zdennis]
+
 * Added db:drop:all to drop all databases declared in config/database.yml [DHH]
 
 * Use attribute pairs instead of the migration name to create add and remove column migrations.  Closes #9166 [lifofifo]
diff --git a/railties/lib/initializer.rb b/railties/lib/initializer.rb
index d55352d6a2..4339c4b996 100644
--- a/railties/lib/initializer.rb
+++ b/railties/lib/initializer.rb
@@ -325,7 +325,9 @@ module Rails
 
     # Fires the user-supplied after_initialize block (Configuration#after_initialize)
     def after_initialize
-      configuration.after_initialize_block.call if configuration.after_initialize_block
+      configuration.after_initialize_blocks.each do |block|
+        block.call
+      end
     end
 
     def load_application_initializers
@@ -515,16 +517,16 @@ module Rails
       ::RAILS_ENV
     end
 
-    # Sets a block which will be executed after rails has been fully initialized.
+    # Adds a block which will be executed after rails has been fully initialized.
     # Useful for per-environment configuration which depends on the framework being
     # fully initialized.
     def after_initialize(&after_initialize_block)
-      @after_initialize_block = after_initialize_block
+      after_initialize_blocks << after_initialize_block if after_initialize_block
     end
 
-    # Returns the block set in Configuration#after_initialize
-    def after_initialize_block
-      @after_initialize_block
+    # Returns the blocks added with Configuration#after_initialize
+    def after_initialize_blocks
+      @after_initialize_blocks ||= []
     end
 
     # Add a preparation callback that will run before every request in development
diff --git a/railties/test/initializer_test.rb b/railties/test/initializer_test.rb
index cf333e878e..c474f0bc05 100644
--- a/railties/test/initializer_test.rb
+++ b/railties/test/initializer_test.rb
@@ -1,15 +1,16 @@
 require "#{File.dirname(__FILE__)}/abstract_unit"
 require 'initializer'
 
-class InitializerTest < Test::Unit::TestCase
-  class ConfigurationMock < Rails::Configuration
-    attr_reader :environment_path
+class ConfigurationMock < Rails::Configuration
+  attr_reader :environment_path
 
-    def initialize(envpath)
-      super()
-      @environment_path = envpath
-    end
+  def initialize(envpath)
+    super()
+    @environment_path = envpath
   end
+end
+
+class Initializer_load_environment_Test < Test::Unit::TestCase
 
   def test_load_environment_with_constant
     config = ConfigurationMock.new("#{File.dirname(__FILE__)}/fixtures/environment_with_constant.rb")
@@ -19,4 +20,65 @@ class InitializerTest < Test::Unit::TestCase
   ensure
     $initialize_test_set_from_env = nil
   end
+
+end
+
+class Initializer_after_initialize_with_blocks_environment_Test < Test::Unit::TestCase
+  def setup
+    config = ConfigurationMock.new("")
+    config.after_initialize do
+      $test_after_initialize_block1 = "success"
+    end
+    config.after_initialize do
+      $test_after_initialize_block2 = "congratulations"
+    end    
+    assert_nil $test_after_initialize_block1
+    assert_nil $test_after_initialize_block2    
+
+    Rails::Initializer.run(:after_initialize, config)
+  end
+  
+  def teardown
+    $test_after_initialize_block1 = nil
+    $test_after_initialize_block2 = nil    
+  end
+
+  def test_should_have_called_the_first_after_initialize_block
+    assert_equal "success", $test_after_initialize_block1
+  end
+  
+  def test_should_have_called_the_second_after_initialize_block
+    assert_equal "congratulations", $test_after_initialize_block2
+  end
+end
+  
+class Initializer_after_initialize_with_no_block_environment_Test < Test::Unit::TestCase
+
+  def setup
+    config = ConfigurationMock.new("")
+    config.after_initialize do
+      $test_after_initialize_block1 = "success"
+    end
+    config.after_initialize # don't pass a block, this is what we're testing!
+    config.after_initialize do
+      $test_after_initialize_block2 = "congratulations"
+    end    
+    assert_nil $test_after_initialize_block1
+
+    Rails::Initializer.run(:after_initialize, config)
+  end
+
+  def teardown
+    $test_after_initialize_block1 = nil
+    $test_after_initialize_block2 = nil    
+  end
+
+  def test_should_have_called_the_first_after_initialize_block
+    assert_equal "success", $test_after_initialize_block1, "should still get set"
+  end
+
+  def test_should_have_called_the_first_after_initialize_block
+    assert_equal "congratulations", $test_after_initialize_block2
+  end
+
 end