diff --git a/servo/components/compositing/compositor.rs b/servo/components/compositing/compositor.rs
index 524f59585c22..c2c38f7bc97f 100644
--- a/servo/components/compositing/compositor.rs
+++ b/servo/components/compositing/compositor.rs
@@ -28,14 +28,14 @@ use layers::rendergl::RenderContext;
 use layers::scene::Scene;
 use layout_traits::LayoutControlChan;
 use msg::constellation_msg::{Image, PixelFormat};
-use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData, MouseButton};
+use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData};
 use msg::constellation_msg::{NavigationDirection, PipelineId, WindowSizeData};
 use pipeline::CompositionPipeline;
 use profile_traits::mem::{self, ReportKind, Reporter, ReporterRequest};
 use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::CompositorEvent::{MouseMoveEvent, TouchEvent};
 use script_traits::{AnimationState, ConstellationControlMsg, LayoutControlMsg};
-use script_traits::{TouchEventType, TouchId};
+use script_traits::{MouseButton, TouchEventType, TouchId};
 use scrolling::ScrollingTimerProxy;
 use std::collections::hash_map::Entry::{Occupied, Vacant};
 use std::collections::{HashMap, HashSet};
diff --git a/servo/components/compositing/windowing.rs b/servo/components/compositing/windowing.rs
index 0dc4e1e46c8b..181d7433f0fc 100644
--- a/servo/components/compositing/windowing.rs
+++ b/servo/components/compositing/windowing.rs
@@ -11,9 +11,9 @@ use euclid::size::TypedSize2D;
 use euclid::{Point2D, Size2D};
 use layers::geometry::DevicePixel;
 use layers::platform::surface::NativeDisplay;
-use msg::constellation_msg::{Key, KeyModifiers, KeyState, MouseButton};
+use msg::constellation_msg::{Key, KeyModifiers, KeyState};
 use net_traits::net_error_list::NetError;
-use script_traits::{TouchEventType, TouchId};
+use script_traits::{MouseButton, TouchEventType, TouchId};
 use std::fmt::{Debug, Error, Formatter};
 use std::rc::Rc;
 use url::Url;
diff --git a/servo/components/msg/constellation_msg.rs b/servo/components/msg/constellation_msg.rs
index 5794453cccb9..1fdb333da3b6 100644
--- a/servo/components/msg/constellation_msg.rs
+++ b/servo/components/msg/constellation_msg.rs
@@ -200,17 +200,6 @@ bitflags! {
     }
 }
 
-/// The mouse button involved in the event.
-#[derive(Clone, Copy, Debug, Deserialize, Serialize)]
-pub enum MouseButton {
-    /// The left mouse button.
-    Left,
-    /// The middle mouse button.
-    Middle,
-    /// The right mouse button.
-    Right,
-}
-
 #[derive(Deserialize, Serialize)]
 pub enum WebDriverCommandMsg {
     LoadUrl(PipelineId, LoadData, IpcSender<LoadStatus>),
diff --git a/servo/components/script/dom/document.rs b/servo/components/script/dom/document.rs
index 45918e7fe53c..aeceb32cf8bd 100644
--- a/servo/components/script/dom/document.rs
+++ b/servo/components/script/dom/document.rs
@@ -82,13 +82,13 @@ use layout_interface::{HitTestResponse, MouseOverResponse};
 use layout_interface::{LayoutChan, Msg, ReflowQueryType};
 use msg::constellation_msg::{ALT, CONTROL, SHIFT, SUPER};
 use msg::constellation_msg::{ConstellationChan, Key, KeyModifiers, KeyState};
-use msg::constellation_msg::{MouseButton, PipelineId, SubpageId};
+use msg::constellation_msg::{PipelineId, SubpageId};
 use net_traits::ControlMsg::{GetCookiesForUrl, SetCookiesForUrl};
 use net_traits::CookieSource::NonHTTP;
 use net_traits::{AsyncResponseTarget, PendingAsyncLoad};
 use num::ToPrimitive;
 use script_thread::{MainThreadScriptMsg, Runnable};
-use script_traits::{AnimationState, MouseEventType, MozBrowserEvent};
+use script_traits::{AnimationState, MouseButton, MouseEventType, MozBrowserEvent};
 use script_traits::{ScriptMsg as ConstellationMsg, ScriptToCompositorMsg};
 use script_traits::{TouchEventType, TouchId, UntrustedNodeAddress};
 use std::ascii::AsciiExt;
diff --git a/servo/components/script/script_thread.rs b/servo/components/script/script_thread.rs
index 96b5fb993491..d4339cb2b05a 100644
--- a/servo/components/script/script_thread.rs
+++ b/servo/components/script/script_thread.rs
@@ -64,8 +64,7 @@ use layout_interface::{self, LayoutChan, NewLayoutThreadInfo, ScriptLayoutChan};
 use libc;
 use mem::heap_size_of_self_and_children;
 use msg::constellation_msg::{ConstellationChan, LoadData};
-use msg::constellation_msg::{MouseButton, PipelineId};
-use msg::constellation_msg::{PipelineNamespace};
+use msg::constellation_msg::{PipelineId, PipelineNamespace};
 use msg::constellation_msg::{SubpageId, WindowSizeData};
 use msg::webdriver_msg::WebDriverScriptCommand;
 use net_traits::LoadData as NetLoadData;
@@ -81,7 +80,7 @@ use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::CompositorEvent::{KeyEvent, MouseButtonEvent, MouseMoveEvent, ResizeEvent};
 use script_traits::CompositorEvent::{TouchEvent};
 use script_traits::{CompositorEvent, ConstellationControlMsg, EventResult};
-use script_traits::{InitialScriptState, MouseEventType, MozBrowserEvent, NewLayoutInfo};
+use script_traits::{InitialScriptState, MouseButton, MouseEventType, MozBrowserEvent, NewLayoutInfo};
 use script_traits::{LayoutMsg, OpaqueScriptLayoutChannel, ScriptMsg as ConstellationMsg};
 use script_traits::{ScriptThreadFactory, ScriptToCompositorMsg, TimerEvent, TimerEventRequest, TimerSource};
 use script_traits::{TouchEventType, TouchId};
diff --git a/servo/components/script_traits/lib.rs b/servo/components/script_traits/lib.rs
index 93db6cd52d26..a4d07966028e 100644
--- a/servo/components/script_traits/lib.rs
+++ b/servo/components/script_traits/lib.rs
@@ -40,7 +40,7 @@ use gfx_traits::LayerId;
 use ipc_channel::ipc::{IpcReceiver, IpcSender};
 use libc::c_void;
 use msg::constellation_msg::{ConstellationChan, Failure, PipelineId, WindowSizeData};
-use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData, MouseButton};
+use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData};
 use msg::constellation_msg::{PipelineNamespaceId, SubpageId};
 use msg::webdriver_msg::WebDriverScriptCommand;
 use net_traits::ResourceThread;
@@ -189,6 +189,17 @@ pub enum TouchEventType {
 #[derive(Clone, Copy, Debug, Eq, PartialEq, Deserialize, Serialize)]
 pub struct TouchId(pub i32);
 
+/// The mouse button involved in the event.
+#[derive(Clone, Copy, Debug, Deserialize, Serialize)]
+pub enum MouseButton {
+    /// The left mouse button.
+    Left,
+    /// The middle mouse button.
+    Middle,
+    /// The right mouse button.
+    Right,
+}
+
 /// The types of mouse events
 #[derive(Deserialize, HeapSizeOf, Serialize)]
 pub enum MouseEventType {
diff --git a/servo/components/script_traits/script_msg.rs b/servo/components/script_traits/script_msg.rs
index cc2104daf711..03a925c166ef 100644
--- a/servo/components/script_traits/script_msg.rs
+++ b/servo/components/script_traits/script_msg.rs
@@ -5,6 +5,7 @@
 use AnimationState;
 use DocumentState;
 use IFrameLoadInfo;
+use MouseButton;
 use MouseEventType;
 use MozBrowserEvent;
 use canvas_traits::CanvasMsg;
@@ -12,7 +13,7 @@ use euclid::point::Point2D;
 use euclid::size::Size2D;
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::{Failure, NavigationDirection, PipelineId};
-use msg::constellation_msg::{LoadData, MouseButton, SubpageId};
+use msg::constellation_msg::{LoadData, SubpageId};
 use offscreen_gl_context::GLContextAttributes;
 use style_traits::viewport::ViewportConstraints;
 use url::Url;
diff --git a/servo/ports/cef/browser_host.rs b/servo/ports/cef/browser_host.rs
index 7dd6830fda1a..73ddfdb06761 100644
--- a/servo/ports/cef/browser_host.rs
+++ b/servo/ports/cef/browser_host.rs
@@ -14,7 +14,8 @@ use compositing::windowing::{WindowEvent, MouseWindowEvent};
 use euclid::point::Point2D;
 use euclid::size::Size2D;
 use libc::{c_double, c_int};
-use msg::constellation_msg::{self, KeyModifiers, KeyState, MouseButton};
+use msg::constellation_msg::{self, KeyModifiers, KeyState};
+use script_traits::MouseButton;
 use std::cell::{Cell, RefCell};
 
 pub struct ServoCefBrowserHost {
diff --git a/servo/ports/glutin/window.rs b/servo/ports/glutin/window.rs
index 217fd7c51575..542ab5d45977 100644
--- a/servo/ports/glutin/window.rs
+++ b/servo/ports/glutin/window.rs
@@ -253,7 +253,7 @@ impl Window {
 
     /// Helper function to handle a click
     fn handle_mouse(&self, button: glutin::MouseButton, action: glutin::ElementState, x: i32, y: i32) {
-        use msg::constellation_msg::MouseButton;
+        use script_traits::MouseButton;
 
         // FIXME(tkuehn): max pixel dist should be based on pixel density
         let max_pixel_dist = 10f64;
diff --git a/servo/ports/gonk/Cargo.lock b/servo/ports/gonk/Cargo.lock
index 65a246abad50..a8d0d0bc0c4a 100644
--- a/servo/ports/gonk/Cargo.lock
+++ b/servo/ports/gonk/Cargo.lock
@@ -16,6 +16,7 @@ dependencies = [
  "net_traits 0.0.1",
  "profile 0.0.1",
  "script 0.0.1",
+ "script_traits 0.0.1",
  "servo 0.0.1",
  "servo-egl 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/servo/ports/gonk/Cargo.toml b/servo/ports/gonk/Cargo.toml
index 6e6eac6cf97e..ac810b8faa9f 100644
--- a/servo/ports/gonk/Cargo.toml
+++ b/servo/ports/gonk/Cargo.toml
@@ -18,6 +18,9 @@ path = "../../components/msg"
 [dependencies.script]
 path = "../../components/script"
 
+[dependencies.script_traits]
+path = "../../components/script_traits"
+
 [dependencies.net_traits]
 path = "../../components/net_traits"
 
diff --git a/servo/ports/gonk/src/input.rs b/servo/ports/gonk/src/input.rs
index b296db77583b..e40900f7acf5 100644
--- a/servo/ports/gonk/src/input.rs
+++ b/servo/ports/gonk/src/input.rs
@@ -6,7 +6,7 @@ use compositing::windowing::{WindowEvent, MouseWindowEvent};
 use errno::errno;
 use euclid::point::Point2D;
 use libc::{c_int, c_long, time_t};
-use msg::constellation_msg::MouseButton;
+use script_traits::MouseButton;
 use std::fs::File;
 use std::io::Read;
 use std::mem::{size_of, transmute, zeroed};
diff --git a/servo/ports/gonk/src/main.rs b/servo/ports/gonk/src/main.rs
index 57728f92f816..75b31dfa71a3 100644
--- a/servo/ports/gonk/src/main.rs
+++ b/servo/ports/gonk/src/main.rs
@@ -33,6 +33,7 @@ extern crate layers;
 extern crate libc;
 extern crate msg;
 extern crate net_traits;
+extern crate script_traits;
 extern crate servo;
 extern crate time;
 extern crate url;