diff --git a/lib/vagrant/action/builtin.rb b/lib/vagrant/action/builtin.rb
index 6cfd620b7..ec5f099c8 100644
--- a/lib/vagrant/action/builtin.rb
+++ b/lib/vagrant/action/builtin.rb
@@ -23,6 +23,7 @@ module Vagrant
         use VM::HostName
         use VM::Network
         use VM::Customize
+        use VM::Modify
         use VM::Boot
       end)
 
@@ -73,6 +74,7 @@ module Vagrant
         use Action[:halt]
         use VM::ClearForwardedPorts
         use VM::ClearSharedFolders
+        use VM::Modify
         use VM::Export
         use VM::PackageVagrantfile
         use VM::Package
diff --git a/lib/vagrant/action/vm.rb b/lib/vagrant/action/vm.rb
index c1e3ea2c2..b8b43a9af 100644
--- a/lib/vagrant/action/vm.rb
+++ b/lib/vagrant/action/vm.rb
@@ -18,6 +18,7 @@ module Vagrant
       autoload :HostName,            'vagrant/action/vm/host_name'
       autoload :Import,              'vagrant/action/vm/import'
       autoload :MatchMACAddress,     'vagrant/action/vm/match_mac_address'
+      autoload :Modify,              'vagrant/action/vm/modify'
       autoload :Network,             'vagrant/action/vm/network'
       autoload :NFS,                 'vagrant/action/vm/nfs'
       autoload :Package,             'vagrant/action/vm/package'
diff --git a/lib/vagrant/action/vm/customize.rb b/lib/vagrant/action/vm/customize.rb
index 3068e112d..2cce925e2 100644
--- a/lib/vagrant/action/vm/customize.rb
+++ b/lib/vagrant/action/vm/customize.rb
@@ -7,11 +7,15 @@ module Vagrant
         end
 
         def call(env)
-          if !env.env.config.vm.proc_stack.empty?
-            env.ui.info I18n.t("vagrant.actions.vm.customize.running")
-            env.env.config.vm.run_procs!(env["vm"].vm)
-            env["vm"].vm.save
-            env["vm"].reload!
+          if !env["config"].vm.proc_stack.empty?
+            # Create the proc which runs all of our procs
+            proc = lambda do |vm|
+              env.ui.info I18n.t("vagrant.actions.vm.customize.running")
+              env["config"].vm.run_procs!(vm)
+            end
+
+            # Add it to modify sequence
+            env["vm.modify"].call(proc)
           end
 
           @app.call(env)
diff --git a/lib/vagrant/action/vm/match_mac_address.rb b/lib/vagrant/action/vm/match_mac_address.rb
index 2db2d85d9..4ca995be9 100644
--- a/lib/vagrant/action/vm/match_mac_address.rb
+++ b/lib/vagrant/action/vm/match_mac_address.rb
@@ -9,11 +9,15 @@ module Vagrant
         def call(env)
           raise Errors::VMBaseMacNotSpecified if !env.env.config.vm.base_mac
 
-          env["config"].vm.customize do |vm|
+          # Create the proc which we want to use to modify the virtual machine
+          proc = lambda do |vm|
             env.ui.info I18n.t("vagrant.actions.vm.match_mac.matching")
             vm.network_adapters.first.mac_address = env["config"].vm.base_mac
           end
 
+          # Add the proc to the modification chain
+          env["vm.modify"].call(proc)
+
           @app.call(env)
         end
       end
diff --git a/lib/vagrant/action/vm/modify.rb b/lib/vagrant/action/vm/modify.rb
new file mode 100644
index 000000000..5f6895d66
--- /dev/null
+++ b/lib/vagrant/action/vm/modify.rb
@@ -0,0 +1,37 @@
+module Vagrant
+  class Action
+    module VM
+      # This class allows other actions on the virtual machine object
+      # to be consolidated under a single write lock. This vastly speeds
+      # up modification of virtual machines. This should be used whereever
+      # possible when dealing with virtual machine modifications.
+      class Modify
+        include Util::StackedProcRunner
+
+        def initialize(app, env)
+          @app = app
+
+          # Initialize the proc_stack, which should already be empty
+          # but just making sure here.
+          proc_stack.clear
+
+          # Create the lambda in the environment which is to be called
+          # to add new procs to the modification sequence.
+          env["vm.modify"] = lambda do |*procs|
+            procs.each { |p| push_proc(&p) }
+          end
+        end
+
+        def call(env)
+          # Run the procs we have saved up, save the machine, and reload
+          # to verify we get the new settings
+          run_procs!(env["vm"].vm)
+          env["vm"].vm.save
+          env["vm"].reload!
+
+          @app.call(env)
+        end
+      end
+    end
+  end
+end
diff --git a/test/vagrant/action/vm/customize_test.rb b/test/vagrant/action/vm/customize_test.rb
index cdbf0bd6b..aede1c0db 100644
--- a/test/vagrant/action/vm/customize_test.rb
+++ b/test/vagrant/action/vm/customize_test.rb
@@ -8,23 +8,29 @@ class CustomizeVMActionTest < Test::Unit::TestCase
 
     @vm = mock("vm")
     @env["vm"] = @vm
+    @env["vm.modify"] = mock("proc")
 
     @internal_vm = mock("internal")
     @vm.stubs(:vm).returns(@internal_vm)
   end
 
   should "not run anything if no customize blocks exist" do
-    @env.env.config.vm.proc_stack.clear
-    @internal_vm.expects(:save).never
+    @env["config"].vm.proc_stack.clear
+    @env["vm.modify"].expects(:call).never
     @app.expects(:call).with(@env).once
     @instance.call(@env)
   end
 
   should "run the VM customization procs then save the VM" do
-    @env.env.config.vm.customize { |vm| }
-    @env.env.config.vm.expects(:run_procs!).with(@internal_vm)
-    @internal_vm.expects(:save).once
-    @env["vm"].expects(:reload!).once
+    ran = false
+    @env["config"].vm.customize { |vm| }
+    @env["config"].vm.expects(:run_procs!).with(@internal_vm)
+
+    @env["vm.modify"].expects(:call).with() do |proc|
+      proc.call(@internal_vm)
+      true
+    end
+
     @app.expects(:call).with(@env).once
     @instance.call(@env)
   end
diff --git a/test/vagrant/action/vm/match_mac_address_test.rb b/test/vagrant/action/vm/match_mac_address_test.rb
index b091b55f0..a75fc051c 100644
--- a/test/vagrant/action/vm/match_mac_address_test.rb
+++ b/test/vagrant/action/vm/match_mac_address_test.rb
@@ -22,7 +22,11 @@ class MatchMACAddressVMActionTest < Test::Unit::TestCase
     @internal_vm.expects(:network_adapters).returns([nic]).once.in_sequence(update_seq)
     @app.expects(:call).with(@env).once.in_sequence(update_seq)
 
-    @env["config"].vm.expects(:customize).yields(@internal_vm)
+    @env["vm.modify"].expects(:call).with() do |proc|
+      proc.call(@internal_vm)
+      true
+    end
+
     @instance.call(@env)
   end
 
diff --git a/test/vagrant/action/vm/modify_test.rb b/test/vagrant/action/vm/modify_test.rb
new file mode 100644
index 000000000..2c1aa437e
--- /dev/null
+++ b/test/vagrant/action/vm/modify_test.rb
@@ -0,0 +1,38 @@
+require "test_helper"
+
+class ModifyVMActionTest < Test::Unit::TestCase
+  setup do
+    @klass = Vagrant::Action::VM::Modify
+    @app, @env = action_env
+
+    @vm = mock("vm")
+    @vm.stubs(:ssh).returns(mock("ssh"))
+    @env["vm"] = @vm
+
+    @internal_vm = mock("internal")
+    @vm.stubs(:vm).returns(@internal_vm)
+
+    @instance = @klass.new(@app, @env)
+  end
+
+  context "initialization" do
+    should "have the vm.modify function setup in the environment" do
+      assert @env.has_key?("vm.modify")
+    end
+  end
+
+  context "calling" do
+    should "run the procs with the VM as an argument and save the VM" do
+      seq = sequence("procseq")
+
+      proc = Proc.new { |vm| }
+      @env["vm.modify"].call(proc)
+
+      proc.expects(:call).with(@internal_vm).once.in_sequence(seq)
+      @internal_vm.expects(:save).once.in_sequence(seq)
+      @vm.expects(:reload!).once.in_sequence(seq)
+
+      @instance.call(@env)
+    end
+  end
+end