diff --git a/components/embedder_traits/lib.rs b/components/embedder_traits/lib.rs
index 340eb674054..9122a76f0ef 100644
--- a/components/embedder_traits/lib.rs
+++ b/components/embedder_traits/lib.rs
@@ -84,6 +84,8 @@ pub enum EmbedderMsg {
     Alert(String, IpcSender<()>),
     /// Wether or not to follow a link
     AllowNavigation(ServoUrl, IpcSender<bool>),
+    /// Wether or not to unload a document
+    AllowUnload(IpcSender<bool>),
     /// Sends an unconsumed key event back to the embedder.
     KeyEvent(Option<char>, Key, KeyState, KeyModifiers),
     /// Changes the cursor.
@@ -122,6 +124,7 @@ impl Debug for EmbedderMsg {
             EmbedderMsg::MoveTo(..) => write!(f, "MoveTo"),
             EmbedderMsg::ResizeTo(..) => write!(f, "ResizeTo"),
             EmbedderMsg::Alert(..) => write!(f, "Alert"),
+            EmbedderMsg::AllowUnload(..) => write!(f, "AllowUnload"),
             EmbedderMsg::AllowNavigation(..) => write!(f, "AllowNavigation"),
             EmbedderMsg::KeyEvent(..) => write!(f, "KeyEvent"),
             EmbedderMsg::SetCursor(..) => write!(f, "SetCursor"),
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 58c9df6d1bf..dc9eae886bb 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -10,8 +10,10 @@ use dom::attr::Attr;
 use dom::beforeunloadevent::BeforeUnloadEvent;
 use dom::bindings::callback::ExceptionHandling;
 use dom::bindings::cell::DomRefCell;
+use dom::bindings::codegen::Bindings::BeforeUnloadEventBinding::BeforeUnloadEventBinding::BeforeUnloadEventMethods;
 use dom::bindings::codegen::Bindings::DocumentBinding;
 use dom::bindings::codegen::Bindings::DocumentBinding::{DocumentMethods, DocumentReadyState, ElementCreationOptions};
+use dom::bindings::codegen::Bindings::EventBinding::EventBinding::EventMethods;
 use dom::bindings::codegen::Bindings::HTMLIFrameElementBinding::HTMLIFrameElementBinding::HTMLIFrameElementMethods;
 use dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
 use dom::bindings::codegen::Bindings::NodeFilterBinding::NodeFilter;
@@ -95,7 +97,7 @@ use fetch::FetchCanceller;
 use html5ever::{LocalName, Namespace, QualName};
 use hyper::header::{Header, SetCookie};
 use hyper_serde::Serde;
-use ipc_channel::ipc::IpcSender;
+use ipc_channel::ipc::{self, IpcSender};
 use js::jsapi::{JSContext, JSObject, JSRuntime};
 use js::jsapi::JS_GetRuntime;
 use metrics::{InteractiveFlag, InteractiveMetrics, InteractiveWindow, ProfilerMetadataFactory, ProgressiveWebMetric};
@@ -108,7 +110,7 @@ use net_traits::pub_domains::is_pub_domain;
 use net_traits::request::RequestInit;
 use net_traits::response::HttpsState;
 use num_traits::ToPrimitive;
-use profile_traits::ipc;
+use profile_traits::ipc as profile_ipc;
 use profile_traits::time::{TimerMetadata, TimerMetadataFrameType, TimerMetadataReflowType};
 use ref_slice::ref_slice;
 use script_layout_interface::message::{Msg, NodesFromPointQueryType, QueryMsg, ReflowGoal};
@@ -1665,7 +1667,15 @@ impl Document {
         // Step 7
         self.salvageable.set(!has_listeners);
         let mut can_unload = true;
-        // TODO: Step 8 send a message to embedder to prompt user.
+        // TODO: Step 8, also check sandboxing modals flag.
+        let default_prevented = event.DefaultPrevented();
+        let return_value_not_empty = !event.downcast::<BeforeUnloadEvent>().unwrap().ReturnValue().is_empty();
+        if default_prevented || return_value_not_empty {
+            let (chan, port) = ipc::channel().expect("Failed to create IPC channel!");
+            let msg = EmbedderMsg::AllowUnload(chan);
+            self.send_to_embedder(msg);
+            can_unload = port.recv().unwrap();
+        }
         // Step 9
         if !recursive_flag {
             for iframe in self.iter_iframes() {
@@ -3638,7 +3648,7 @@ impl DocumentMethods for Document {
         }
 
         let url = self.url();
-        let (tx, rx) = ipc::channel(self.global().time_profiler_chan().clone()).unwrap();
+        let (tx, rx) = profile_ipc::channel(self.global().time_profiler_chan().clone()).unwrap();
         let _ = self.window
             .upcast::<GlobalScope>()
             .resource_threads()
diff --git a/ports/servo/browser.rs b/ports/servo/browser.rs
index f874baa346c..996ad276a8d 100644
--- a/ports/servo/browser.rs
+++ b/ports/servo/browser.rs
@@ -266,6 +266,13 @@ impl Browser {
                         self.event_queue.push(WindowEvent::SendError(browser_id, reason));
                     }
                 }
+                EmbedderMsg::AllowUnload(sender) => {
+                    // Always allow unload for now.
+                    if let Err(e) = sender.send(true) {
+                        let reason = format!("Failed to send AllowUnload response: {}", e);
+                        self.event_queue.push(WindowEvent::SendError(browser_id, reason));
+                    }
+                }
                 EmbedderMsg::AllowNavigation(_url, response_chan) => {
                     if let Err(e) = response_chan.send(true) {
                         warn!("Failed to send allow_navigation() response: {}", e);