diff --git a/lib/vagrant/action/builtin.rb b/lib/vagrant/action/builtin.rb
index 2941263ef..fe0e38c43 100644
--- a/lib/vagrant/action/builtin.rb
+++ b/lib/vagrant/action/builtin.rb
@@ -8,6 +8,7 @@ module Vagrant
       up = Builder.new do
         use VM::Import
         use VM::Customize
+        use VM::ForwardPorts
       end
 
       register :up, up
diff --git a/lib/vagrant/action/vm/forward_ports.rb b/lib/vagrant/action/vm/forward_ports.rb
new file mode 100644
index 000000000..804803bdb
--- /dev/null
+++ b/lib/vagrant/action/vm/forward_ports.rb
@@ -0,0 +1,145 @@
+module Vagrant
+  class Action
+    module VM
+      class ForwardPorts
+        def initialize(app,env)
+          @app = app
+          @env = env
+
+          external_collision_check
+        end
+
+        #--------------------------------------------------------------
+        # Prepare Helpers - These functions are not involved in actually
+        # executing the action
+        #--------------------------------------------------------------
+
+        # This method checks for any port collisions with any VMs
+        # which are already created (by Vagrant or otherwise).
+        # report the collisions detected or will attempt to fix them
+        # automatically if the port is configured to do so.
+        def external_collision_check
+          existing = used_ports
+          @env.env.config.vm.forwarded_ports.each do |name, options|
+            if existing.include?(options[:hostport].to_s)
+              handle_collision(name, options, existing)
+            end
+          end
+        end
+
+        # Handles any collisions. This method will either attempt to
+        # fix the collision automatically or will raise an error if
+        # auto fixing is disabled.
+        def handle_collision(name, options, existing_ports)
+          if !options[:auto]
+            # Auto fixing is disabled for this port forward, so we
+            # must throw an error so the user can fix it.
+            return @env.error!(:vm_port_collision, :name => name, :hostport => options[:hostport].to_s, :guestport => options[:guestport].to_s, :adapter => options[:adapter])
+          end
+
+          # Get the auto port range and get rid of the used ports and
+          # ports which are being used in other forwards so we're just
+          # left with available ports.
+          range = @env.env.config.vm.auto_port_range.to_a
+          range -= @env.env.config.vm.forwarded_ports.collect { |n, o| o[:hostport].to_i }
+          range -= existing_ports
+
+          if range.empty?
+            return @env.error!(:vm_port_auto_empty, :vm_name => @env["vm"].name, :name => name, :options => options)
+          end
+
+          # Set the port up to be the first one and add that port to
+          # the used list.
+          options[:hostport] = range.shift
+          existing_ports << options[:hostport]
+
+          # Notify the user
+          @env.logger.info "Fixed port collision: #{name} now on port #{options[:hostport]}"
+        end
+
+        #--------------------------------------------------------------
+        # Execution
+        #--------------------------------------------------------------
+        def call(env)
+          @env = env
+
+          clear
+          forward_ports
+
+          @app.call(env)
+        end
+
+        def clear
+          if used_ports.length > 0
+            @env.logger.info "Deleting any previously set forwarded ports..."
+            clear_ports
+            @env["vm"].reload!
+          end
+        end
+
+        def forward_ports
+          @env.logger.info "Forwarding ports..."
+
+          @env.env.config.vm.forwarded_ports.each do |name, options|
+            adapter = options[:adapter]
+
+            # Assuming the only reason to establish port forwarding is because the VM is using Virtualbox NAT networking.
+            # Host-only or Bridged networking don't require port-forwarding and establishing forwarded ports on these
+            # attachment types has uncertain behaviour.
+            if @env["vm"].vm.network_adapters[adapter].attachment_type == :nat
+              @env.logger.info "Forwarding \"#{name}\": #{options[:guestport]} on adapter \##{adapter+1} => #{options[:hostport]}"
+              forward_port(name, options)
+            else
+              @env.logger.info "VirtualBox adapter \##{adapter+1} not configured as \"NAT\"."
+              @env.logger.info "Skipped port forwarding \"#{name}\": #{options[:guestport]} on adapter\##{adapter+1} => #{options[:hostport]}"
+            end
+          end
+
+          @env["vm"].vm.save
+          @env["vm"].reload!
+        end
+
+        #--------------------------------------------------------------
+        # General Helpers
+        #--------------------------------------------------------------
+
+        # Returns an array of used ports. This method is implemented
+        # differently depending on the VirtualBox version, but the
+        # behavior is the same.
+        #
+        # @return [Array<String>]
+        def used_ports
+          result = VirtualBox::VM.all.collect do |vm|
+            if vm.running? && vm.uuid != @env["vm"].uuid
+              vm.network_adapters.collect do |na|
+                na.nat_driver.forwarded_ports.collect do |fp|
+                  fp.hostport.to_s
+                end
+              end
+            end
+          end
+
+          result.flatten.uniq
+        end
+
+        # Deletes existing forwarded ports.
+        def clear_ports
+          @env["vm"].vm.network_adapters.each do |na|
+            na.nat_driver.forwarded_ports.dup.each do |fp|
+              fp.destroy
+            end
+          end
+        end
+
+        # Forwards a port.
+        def forward_port(name, options)
+          port = VirtualBox::NATForwardedPort.new
+          port.name = name
+          port.guestport = options[:guestport]
+          port.hostport = options[:hostport]
+          @env["vm"].vm.network_adapters[options[:adapter]].nat_driver.forwarded_ports << port
+        end
+      end
+    end
+  end
+end
diff --git a/test/vagrant/action/vm/forward_ports_test.rb b/test/vagrant/action/vm/forward_ports_test.rb
new file mode 100644
index 000000000..94490517d
--- /dev/null
+++ b/test/vagrant/action/vm/forward_ports_test.rb
@@ -0,0 +1,270 @@
+require File.join(File.dirname(__FILE__), '..', '..', '..', 'test_helper')
+
+class ForwardPortsVMActionTest < Test::Unit::TestCase
+  setup do
+    @klass = Vagrant::Action::VM::ForwardPorts
+    @app, @env = mock_action_data
+
+    @vm = mock("vm")
+    @vm.stubs(:name).returns("foo")
+    @env["vm"] = @vm
+  end
+
+  context "initializing" do
+    should "call proper methods" do
+      @klass.any_instance.expects(:external_collision_check)
+      @klass.new(@app, @env)
+    end
+  end
+
+  context "checking for colliding external ports" do
+    setup do
+      @env.env.config.vm.forwarded_ports.clear
+      @env.env.config.vm.forward_port("ssh", 22, 2222)
+
+      @used_ports = []
+      @klass.any_instance.stubs(:used_ports).returns(@used_ports)
+      @klass.any_instance.stubs(:handle_collision)
+    end
+
+    should "not raise any errors if no forwarded ports collide" do
+      @used_ports << "80"
+      @klass.new(@app, @env)
+      assert !@env.error?
+    end
+
+    should "handle collision if it happens" do
+      @used_ports << "2222"
+      @klass.any_instance.expects(:handle_collision).with("ssh", anything, anything).once
+      @klass.new(@app, @env)
+      assert !@env.error?
+    end
+  end
+
+  context "with instance" do
+    setup do
+      @klass.any_instance.stubs(:external_collision_check)
+      @instance = @klass.new(@app, @env)
+    end
+
+    context "handling collisions" do
+      setup do
+        @name = :foo
+        @options = {
+          :hostport => 0,
+          :auto => true
+        }
+        @used_ports = [1,2,3]
+
+        @env.env.config.vm.auto_port_range = (1..5)
+      end
+
+      should "error if auto forwarding is disabled" do
+        @options[:auto] = false
+        @instance.handle_collision(@name, @options, @used_ports)
+        assert @env.error?
+        assert_equal :vm_port_collision, @env.error.first
+      end
+
+      should "set the host port to the first available port" do
+        assert_equal 0, @options[:hostport]
+        @instance.handle_collision(@name, @options, @used_ports)
+        assert_equal 4, @options[:hostport]
+      end
+
+      should "add the newly used port to the list of used ports" do
+        assert !@used_ports.include?(4)
+        @instance.handle_collision(@name, @options, @used_ports)
+        assert @used_ports.include?(4)
+      end
+
+      should "not use a host port which is being forwarded later" do
+        @env.env.config.vm.forward_port("http", 80, 4)
+
+        assert_equal 0, @options[:hostport]
+        @instance.handle_collision(@name, @options, @used_ports)
+        assert_equal 5, @options[:hostport]
+      end
+
+      should "raise an exception if there are no auto ports available" do
+        @env.env.config.vm.auto_port_range = (1..3)
+        @instance.handle_collision(@name, @options, @used_ports)
+        assert @env.error?
+        assert_equal :vm_port_auto_empty, @env.error.first
+      end
+    end
+
+    context "calling" do
+      should "clear all previous ports and forward new ports" do
+        exec_seq = sequence("exec_seq")
+        @instance.expects(:clear).once.in_sequence(exec_seq)
+        @instance.expects(:forward_ports).once.in_sequence(exec_seq)
+        @app.expects(:call).once.with(@env).in_sequence(exec_seq)
+        @instance.call(@env)
+      end
+    end
+
+    context "forwarding ports" do
+      setup do
+        @internal_vm = mock("internal_vm")
+        @vm.stubs(:vm).returns(@internal_vm)
+      end
+
+      should "create a port forwarding for the VM" do
+        forwarded_ports = mock("forwarded_ports")
+        network_adapter = mock("network_adapter")
+
+        @internal_vm.stubs(:network_adapters).returns([network_adapter])
+        network_adapter.expects(:attachment_type).returns(:nat)
+
+        @instance.expects(:forward_port).once
+        @internal_vm.expects(:save).once
+        @vm.expects(:reload!).once
+        @instance.forward_ports
+      end
+
+      should "not port forward for non NAT interfaces" do
+        forwarded_ports = mock("forwarded_ports")
+        network_adapter = mock("network_adapter")
+
+        @internal_vm.expects(:network_adapters).returns([network_adapter])
+        network_adapter.expects(:attachment_type).returns(:host_only)
+        @internal_vm.expects(:save).once
+        @vm.expects(:reload!).once
+        @instance.forward_ports
+      end
+    end
+
+    context "clearing forwarded ports" do
+      setup do
+        @instance.stubs(:used_ports).returns([:a])
+        @instance.stubs(:clear_ports)
+      end
+
+      should "call destroy on all forwarded ports" do
+        @instance.expects(:clear_ports).once
+        @vm.expects(:reload!)
+        @instance.clear
+      end
+
+      should "do nothing if there are no forwarded ports" do
+        @instance.stubs(:used_ports).returns([])
+        @vm.expects(:reload!).never
+        @instance.clear
+      end
+    end
+
+    context "getting list of used ports" do
+      setup do
+        @vms = []
+        VirtualBox::VM.stubs(:all).returns(@vms)
+        VirtualBox.stubs(:version).returns("3.1.0")
+        @vm.stubs(:uuid).returns(:bar)
+      end
+
+      def mock_vm(options={})
+        options = {
+          :running? => true,
+          :uuid => :foo
+        }.merge(options)
+
+        vm = mock("vm")
+        options.each do |k,v|
+          vm.stubs(k).returns(v)
+        end
+
+        vm
+      end
+
+      def mock_fp(hostport)
+        fp = mock("fp")
+        fp.stubs(:hostport).returns(hostport.to_s)
+        fp
+      end
+
+      should "ignore VMs which aren't running" do
+        @vms << mock_vm(:running? => false)
+        @vms[0].expects(:forwarded_ports).never
+        @instance.used_ports
+      end
+
+      should "ignore VMs of the same uuid" do
+        @vms << mock_vm(:uuid => @vm.uuid)
+        @vms[0].expects(:forwarded_ports).never
+        @instance.used_ports
+      end
+
+      should "return the forwarded ports for VB 3.2.x" do
+        VirtualBox.stubs(:version).returns("3.2.4")
+        fps = [mock_fp(2222), mock_fp(80)]
+        na = mock("na")
+        ne = mock("ne")
+        na.stubs(:nat_driver).returns(ne)
+        ne.stubs(:forwarded_ports).returns(fps)
+        @vms << mock_vm(:network_adapters => [na])
+        assert_equal %W[2222 80], @instance.used_ports
+      end
+    end
+
+    context "clearing ports" do
+      def mock_fp
+        fp = mock("fp")
+        fp.expects(:destroy).once
+        fp
+      end
+
+      setup do
+        VirtualBox.stubs(:version).returns("3.2.8")
+        @adapters = []
+        @internal_vm = mock("internal_vm")
+        @internal_vm.stubs(:network_adapters).returns(@adapters)
+        @vm.stubs(:vm).returns(@internal_vm)
+      end
+
+      def mock_adapter
+        na = mock("adapter")
+        engine = mock("engine")
+        engine.stubs(:forwarded_ports).returns([mock_fp])
+        na.stubs(:nat_driver).returns(engine)
+        na
+      end
+
+      should "destroy each forwarded port" do
+        @adapters << mock_adapter
+        @adapters << mock_adapter
+        @instance.clear_ports
+      end
+    end
+
+    context "forwarding ports implementation" do
+      setup do
+        VirtualBox.stubs(:version).returns("3.2.8")
+
+        @internal_vm = mock("internal_vm")
+        @vm.stubs(:vm).returns(@internal_vm)
+      end
+
+      should "forward ports" do
+        name, opts = @env.env.config.vm.forwarded_ports.first
+
+        adapters = []
+        adapter = mock("adapter")
+        engine = mock("engine")
+        fps = mock("forwarded ports")
+        adapter.stubs(:nat_driver).returns(engine)
+        engine.stubs(:forwarded_ports).returns(fps)
+        fps.expects(:<<).with do |port|
+          assert_equal name, port.name
+          assert_equal opts[:hostport], port.hostport
+          assert_equal opts[:guestport], port.guestport
+          true
+        end
+
+        adapters[opts[:adapter]] = adapter
+        @internal_vm.stubs(:network_adapters).returns(adapters)
+
+        @instance.forward_port(name, opts)
+      end
+    end
+  end
+end