diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 0b6db7fc68b..9b36649b2e6 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -83,7 +83,7 @@ Fill in the following fields for your Cask:
 | `sha256`           | SHA-256 checksum of the file; checked when the file is downloaded to prevent any funny business (can be omitted with `no_checksum`)
 | __artifact info__  | information about artifacts inside the Cask (can be specified multiple times)
 | `link`             | relative path to a file that should be linked into the `Applications` folder on installation (see __Link Details__ for more information)
-| `install`          | relative path to `pkg` that should be run to install the application
+| `install`          | relative path to `pkg` that should be run to install the application (see __Install Details__ for more information)
 | `uninstall`        | indicates what commands/scripts must be run to uninstall a pkg-based application (see __Uninstall Details__ for more information)
 
 Additional fields you might need for special use-cases:
@@ -242,6 +242,26 @@ link 'TexmakerMacosxLion/texmaker.app'
 
 Linking to the .app file without reference to the containing folder will result in installation failing with a "symlink source is not there" error.
 
+### Install Details
+
+The first argument to `install` should be a relative path to the `pkg` file
+to be installed.  For example:
+
+```ruby
+install 'Vagrant.pkg'
+```
+
+Subsequent arguments to `install` are key/value pairs which modify the
+install process.  Currently supported keys are
+
+  * `:allow_untrusted` -- pass `-allowUntrusted` to `/usr/sbin/installer`
+
+Example:
+
+```ruby
+install 'Soundflower.pkg', :allow_untrusted => true
+```
+
 ### Uninstall Details
 
 A `pkg`-based Cask using `install` will **not** know how to uninstall
diff --git a/lib/cask/artifact/pkg.rb b/lib/cask/artifact/pkg.rb
index 69ec9f1b4df..0771f593b5c 100644
--- a/lib/cask/artifact/pkg.rb
+++ b/lib/cask/artifact/pkg.rb
@@ -31,21 +31,42 @@ class Cask::Artifact::Pkg < Cask::Artifact::Base
     return executable, script_arguments
   end
 
+  def load_pkg_description(pkg_description)
+    @pkg_relative_path = pkg_description.shift
+    @pkg_install_opts = pkg_description.shift
+    if @pkg_install_opts.respond_to?(:keys)
+      @pkg_install_opts.assert_valid_keys( :allow_untrusted )
+    elsif @pkg_install_opts
+      raise "Bad install stanza in Cask #{@cask}"
+    end
+    raise "Bad install stanza in Cask #{@cask}" if pkg_description.nil?
+  end
+
+  def pkg_install_opts(opt)
+    @pkg_install_opts[opt] if @pkg_install_opts.respond_to?(:keys)
+  end
+
+  def pkg_relative_path
+    @pkg_relative_path
+  end
+
   def install
-    @cask.artifacts[:install].each { |pkg| run_installer(pkg) }
+    @cask.artifacts[:install].each { |pkg_description| run_installer(pkg_description) }
   end
 
   def uninstall
     @cask.artifacts[:uninstall].each { |opts| manually_uninstall(opts) }
   end
 
-  def run_installer(pkg_relative_path)
+  def run_installer(pkg_description)
+    load_pkg_description pkg_description
     ohai "Running installer for #{@cask}; your password may be necessary."
     args = [
       '-pkg',    @cask.destination_path.join(pkg_relative_path),
       '-target', '/'
     ]
     args << '-verboseR' if ARGV.verbose?
+    args << '-allowUntrusted' if pkg_install_opts :allow_untrusted
     @command.run!('/usr/sbin/installer', {:sudo => true, :args => args, :print => true})
   end
 
diff --git a/lib/cask/dsl.rb b/lib/cask/dsl.rb
index 426413f188f..1d93a849a4b 100644
--- a/lib/cask/dsl.rb
+++ b/lib/cask/dsl.rb
@@ -75,7 +75,8 @@ module Cask::DSL
       :binary,
       :caskroom_only,
       :input_method,
-      :screen_saver
+      :screen_saver,
+      :install,
     ]
 
     ARTIFACT_TYPES.each do |type|
@@ -85,7 +86,6 @@ module Cask::DSL
     end
 
     SPECIAL_ARTIFACT_TYPES = [
-      :install,
       :nested_container,
       :uninstall
     ]
diff --git a/test/cask/dsl_test.rb b/test/cask/dsl_test.rb
index 4be0adcd843..7cb84d2ae08 100644
--- a/test/cask/dsl_test.rb
+++ b/test/cask/dsl_test.rb
@@ -90,7 +90,7 @@ describe Cask::DSL do
     end
 
     instance = CaskWithInstallables.new
-    Array(instance.artifacts[:install]).sort.must_equal %w[Bar.pkg Foo.pkg]
+    Array(instance.artifacts[:install]).sort.must_equal [['Bar.pkg'], ['Foo.pkg']]
   end
 
   it "prevents defining multiple urls" do