diff --git a/spec/atom-environment-spec.coffee b/spec/atom-environment-spec.coffee
index 3365fc1b0..5d269a3bb 100644
--- a/spec/atom-environment-spec.coffee
+++ b/spec/atom-environment-spec.coffee
@@ -477,8 +477,6 @@ describe "AtomEnvironment", ->
           devMode: atom.inDevMode()
           safeMode: atom.inSafeMode()
 
-
-
   describe "::unloadEditorWindow()", ->
     it "saves the BlobStore so it can be loaded after reload", ->
       configDirPath = temp.mkdirSync('atom-spec-environment')
diff --git a/spec/main-process/atom-application.test.js b/spec/main-process/atom-application.test.js
index 5929b6ac9..1fd1b6a23 100644
--- a/spec/main-process/atom-application.test.js
+++ b/spec/main-process/atom-application.test.js
@@ -207,7 +207,7 @@ describe('AtomApplication', function () {
           sendBackToMainProcess(null)
         })
       })
-      await window1.saveState()
+      await window1.prepareToUnload()
       window1.close()
       await window1.closedPromise
 
@@ -221,7 +221,7 @@ describe('AtomApplication', function () {
         sendBackToMainProcess(textEditor.getText())
       })
       assert.equal(window2Text, 'Hello World! How are you?')
-      await window2.saveState()
+      await window2.prepareToUnload()
       window2.close()
       await window2.closedPromise
 
@@ -354,8 +354,8 @@ describe('AtomApplication', function () {
       ])
 
       await Promise.all([
-        app1Window1.saveState(),
-        app1Window2.saveState()
+        app1Window1.prepareToUnload(),
+        app1Window2.prepareToUnload()
       ])
 
       const atomApplication2 = buildAtomApplication()
@@ -471,7 +471,7 @@ describe('AtomApplication', function () {
       await focusWindow(window2)
       electron.app.quit()
       assert(!electron.app.hasQuitted())
-      await Promise.all([window1.lastSaveStatePromise, window2.lastSaveStatePromise])
+      await Promise.all([window1.lastPrepareToUnloadPromise, window2.lastPrepareToUnloadPromise])
       assert(electron.app.hasQuitted())
     })
   })
diff --git a/spec/pane-container-element-spec.coffee b/spec/pane-container-element-spec.coffee
index 9f25e13eb..7ea1cc8a0 100644
--- a/spec/pane-container-element-spec.coffee
+++ b/spec/pane-container-element-spec.coffee
@@ -149,11 +149,11 @@ describe "PaneContainerElement", ->
       )
       expectPaneScale [leftPane, 0.5], [middlePane, 0.75], [rightPane, 1.75]
 
-      middlePane.close()
-      expectPaneScale [leftPane, 0.44], [rightPane, 1.55]
+      waitsForPromise -> middlePane.close()
+      runs -> expectPaneScale [leftPane, 0.44], [rightPane, 1.55]
 
-      leftPane.close()
-      expectPaneScale [rightPane, 1]
+      waitsForPromise -> leftPane.close()
+      runs -> expectPaneScale [rightPane, 1]
 
     it "splits or closes panes in orthogonal direction that the pane is being dragged", ->
       leftPane = container.getActivePane()
@@ -173,8 +173,8 @@ describe "PaneContainerElement", ->
       expectPaneScale [lowerPane, 1], [leftPane, 1], [leftPane.getParent(), 0.5]
 
       # dynamically close pane, the pane's flexscale will recorver to origin value
-      lowerPane.close()
-      expectPaneScale [leftPane, 0.5], [rightPane, 1.5]
+      waitsForPromise -> lowerPane.close()
+      runs -> expectPaneScale [leftPane, 0.5], [rightPane, 1.5]
 
     it "unsubscribes from mouse events when the pane is detached", ->
       container.getActivePane().splitRight()
diff --git a/spec/pane-container-spec.coffee b/spec/pane-container-spec.coffee
index a232eaecd..587fbae6f 100644
--- a/spec/pane-container-spec.coffee
+++ b/spec/pane-container-spec.coffee
@@ -200,15 +200,17 @@ describe "PaneContainer", ->
 
     it "returns true if the user saves all modified files when prompted", ->
       confirm.andReturn(0)
-      saved = container.confirmClose()
-      expect(saved).toBeTruthy()
-      expect(confirm).toHaveBeenCalled()
+      waitsForPromise ->
+        container.confirmClose().then (saved) ->
+          expect(confirm).toHaveBeenCalled()
+          expect(saved).toBeTruthy()
 
     it "returns false if the user cancels saving any modified file", ->
       confirm.andReturn(1)
-      saved = container.confirmClose()
-      expect(saved).toBeFalsy()
-      expect(confirm).toHaveBeenCalled()
+      waitsForPromise ->
+        container.confirmClose().then (saved) ->
+          expect(confirm).toHaveBeenCalled()
+          expect(saved).toBeFalsy()
 
   describe "::onDidAddPane(callback)", ->
     it "invokes the given callback when panes are added", ->
diff --git a/spec/pane-spec.coffee b/spec/pane-spec.coffee
index 11b80c66c..610f51fc8 100644
--- a/spec/pane-spec.coffee
+++ b/spec/pane-spec.coffee
@@ -460,11 +460,12 @@ describe "Pane", ->
           it "saves the item before destroying it", ->
             itemURI = "test"
             confirm.andReturn(0)
-            pane.destroyItem(item1)
 
-            expect(item1.save).toHaveBeenCalled()
-            expect(item1 in pane.getItems()).toBe false
-            expect(item1.isDestroyed()).toBe true
+            waitsForPromise ->
+              pane.destroyItem(item1).then ->
+                expect(item1.save).toHaveBeenCalled()
+                expect(item1 in pane.getItems()).toBe false
+                expect(item1.isDestroyed()).toBe true
 
         describe "when the item has no uri", ->
           it "presents a save-as dialog, then saves the item with the given uri before removing and destroying it", ->
@@ -472,21 +473,23 @@ describe "Pane", ->
 
             showSaveDialog.andReturn("/selected/path")
             confirm.andReturn(0)
-            pane.destroyItem(item1)
 
-            expect(showSaveDialog).toHaveBeenCalled()
-            expect(item1.saveAs).toHaveBeenCalledWith("/selected/path")
-            expect(item1 in pane.getItems()).toBe false
-            expect(item1.isDestroyed()).toBe true
+            waitsForPromise ->
+              pane.destroyItem(item1).then ->
+                expect(showSaveDialog).toHaveBeenCalled()
+                expect(item1.saveAs).toHaveBeenCalledWith("/selected/path")
+                expect(item1 in pane.getItems()).toBe false
+                expect(item1.isDestroyed()).toBe true
 
       describe "if the [Don't Save] option is selected", ->
         it "removes and destroys the item without saving it", ->
           confirm.andReturn(2)
-          pane.destroyItem(item1)
 
-          expect(item1.save).not.toHaveBeenCalled()
-          expect(item1 in pane.getItems()).toBe false
-          expect(item1.isDestroyed()).toBe true
+          waitsForPromise ->
+            pane.destroyItem(item1).then ->
+              expect(item1.save).not.toHaveBeenCalled()
+              expect(item1 in pane.getItems()).toBe false
+              expect(item1.isDestroyed()).toBe true
 
       describe "if the [Cancel] option is selected", ->
         it "does not save, remove, or destroy the item", ->
@@ -550,11 +553,14 @@ describe "Pane", ->
     it "destroys all items", ->
       pane = new Pane(paneParams(items: [new Item("A"), new Item("B"), new Item("C")]))
       [item1, item2, item3] = pane.getItems()
-      pane.destroyItems()
-      expect(item1.isDestroyed()).toBe true
-      expect(item2.isDestroyed()).toBe true
-      expect(item3.isDestroyed()).toBe true
-      expect(pane.getItems()).toEqual []
+
+      waitsForPromise -> pane.destroyItems()
+
+      runs ->
+        expect(item1.isDestroyed()).toBe true
+        expect(item2.isDestroyed()).toBe true
+        expect(item3.isDestroyed()).toBe true
+        expect(pane.getItems()).toEqual []
 
   describe "::observeItems()", ->
     it "invokes the observer with all current and future items", ->
@@ -620,24 +626,22 @@ describe "Pane", ->
           pane.saveActiveItem()
           expect(showSaveDialog).not.toHaveBeenCalled()
 
-    describe "when the item's saveAs method throws a well-known IO error", ->
-      notificationSpy = null
-      beforeEach ->
-        atom.notifications.onDidAddNotification notificationSpy = jasmine.createSpy()
-
+    describe "when the item's saveAs rejects with a well-known IO error", ->
       it "creates a notification", ->
         pane.getActiveItem().saveAs = ->
           error = new Error("EACCES, permission denied '/foo'")
           error.path = '/foo'
           error.code = 'EACCES'
-          throw error
+          Promise.reject(error)
 
-        pane.saveActiveItem()
-        expect(notificationSpy).toHaveBeenCalled()
-        notification = notificationSpy.mostRecentCall.args[0]
-        expect(notification.getType()).toBe 'warning'
-        expect(notification.getMessage()).toContain 'Permission denied'
-        expect(notification.getMessage()).toContain '/foo'
+        waitsFor (done) ->
+          subscription = atom.notifications.onDidAddNotification (notification) ->
+            expect(notification.getType()).toBe 'warning'
+            expect(notification.getMessage()).toContain 'Permission denied'
+            expect(notification.getMessage()).toContain '/foo'
+            subscription.dispose()
+            done()
+          pane.saveActiveItem()
 
   describe "::saveActiveItemAs()", ->
     pane = null
@@ -661,23 +665,21 @@ describe "Pane", ->
         expect(showSaveDialog).not.toHaveBeenCalled()
 
     describe "when the item's saveAs method throws a well-known IO error", ->
-      notificationSpy = null
-      beforeEach ->
-        atom.notifications.onDidAddNotification notificationSpy = jasmine.createSpy()
-
       it "creates a notification", ->
         pane.getActiveItem().saveAs = ->
           error = new Error("EACCES, permission denied '/foo'")
           error.path = '/foo'
           error.code = 'EACCES'
-          throw error
+          Promise.reject(error)
 
-        pane.saveActiveItemAs()
-        expect(notificationSpy).toHaveBeenCalled()
-        notification = notificationSpy.mostRecentCall.args[0]
-        expect(notification.getType()).toBe 'warning'
-        expect(notification.getMessage()).toContain 'Permission denied'
-        expect(notification.getMessage()).toContain '/foo'
+        waitsFor (done) ->
+          subscription = atom.notifications.onDidAddNotification (notification) ->
+            expect(notification.getType()).toBe 'warning'
+            expect(notification.getMessage()).toContain 'Permission denied'
+            expect(notification.getMessage()).toContain '/foo'
+            subscription.dispose()
+            done()
+          pane.saveActiveItemAs()
 
   describe "::itemForURI(uri)", ->
     it "returns the item for which a call to .getURI() returns the given uri", ->
@@ -787,7 +789,6 @@ describe "Pane", ->
         pane2.moveItemToPane(item5, pane1, 0)
         expect(pane1.getPendingItem()).toEqual item6
 
-
   describe "split methods", ->
     [pane1, item1, container] = []
 
@@ -926,11 +927,10 @@ describe "Pane", ->
       item1.save = jasmine.createSpy("save")
 
       confirm.andReturn(0)
-      pane.close()
-
-      expect(confirm).toHaveBeenCalled()
-      expect(item1.save).toHaveBeenCalled()
-      expect(pane.isDestroyed()).toBe true
+      pane.close().then ->
+        expect(confirm).toHaveBeenCalled()
+        expect(item1.save).toHaveBeenCalled()
+        expect(pane.isDestroyed()).toBe true
 
     it "does not destroy the pane if cancel is called", ->
       pane = new Pane(paneParams(items: [new Item("A"), new Item("B")]))
@@ -941,11 +941,12 @@ describe "Pane", ->
       item1.save = jasmine.createSpy("save")
 
       confirm.andReturn(1)
-      pane.close()
 
-      expect(confirm).toHaveBeenCalled()
-      expect(item1.save).not.toHaveBeenCalled()
-      expect(pane.isDestroyed()).toBe false
+      waitsForPromise ->
+        pane.close().then ->
+          expect(confirm).toHaveBeenCalled()
+          expect(item1.save).not.toHaveBeenCalled()
+          expect(pane.isDestroyed()).toBe false
 
     describe "when item fails to save", ->
       [pane, item1, item2] = []
@@ -972,12 +973,12 @@ describe "Pane", ->
           else
             return 1 # click cancel
 
-        pane.close()
-
-        expect(atom.applicationDelegate.confirm).toHaveBeenCalled()
-        expect(confirmations).toBe(2)
-        expect(item1.save).toHaveBeenCalled()
-        expect(pane.isDestroyed()).toBe false
+        waitsForPromise ->
+          pane.close().then ->
+            expect(atom.applicationDelegate.confirm).toHaveBeenCalled()
+            expect(confirmations).toBe(2)
+            expect(item1.save).toHaveBeenCalled()
+            expect(pane.isDestroyed()).toBe false
 
       it "does destroy the pane if the user saves the file under a new name", ->
         item1.saveAs = jasmine.createSpy("saveAs").andReturn(true)
@@ -989,14 +990,14 @@ describe "Pane", ->
 
         showSaveDialog.andReturn("new/path")
 
-        pane.close()
-
-        expect(atom.applicationDelegate.confirm).toHaveBeenCalled()
-        expect(confirmations).toBe(2)
-        expect(atom.applicationDelegate.showSaveDialog).toHaveBeenCalled()
-        expect(item1.save).toHaveBeenCalled()
-        expect(item1.saveAs).toHaveBeenCalled()
-        expect(pane.isDestroyed()).toBe true
+        waitsForPromise ->
+          pane.close().then ->
+            expect(atom.applicationDelegate.confirm).toHaveBeenCalled()
+            expect(confirmations).toBe(2)
+            expect(atom.applicationDelegate.showSaveDialog).toHaveBeenCalled()
+            expect(item1.save).toHaveBeenCalled()
+            expect(item1.saveAs).toHaveBeenCalled()
+            expect(pane.isDestroyed()).toBe true
 
       it "asks again if the saveAs also fails", ->
         item1.saveAs = jasmine.createSpy("saveAs").andCallFake ->
@@ -1014,14 +1015,14 @@ describe "Pane", ->
 
         showSaveDialog.andReturn("new/path")
 
-        pane.close()
-
-        expect(atom.applicationDelegate.confirm).toHaveBeenCalled()
-        expect(confirmations).toBe(3)
-        expect(atom.applicationDelegate.showSaveDialog).toHaveBeenCalled()
-        expect(item1.save).toHaveBeenCalled()
-        expect(item1.saveAs).toHaveBeenCalled()
-        expect(pane.isDestroyed()).toBe true
+        waitsForPromise ->
+          pane.close().then ->
+            expect(atom.applicationDelegate.confirm).toHaveBeenCalled()
+            expect(confirmations).toBe(3)
+            expect(atom.applicationDelegate.showSaveDialog).toHaveBeenCalled()
+            expect(item1.save).toHaveBeenCalled()
+            expect(item1.saveAs).toHaveBeenCalled()
+            expect(pane.isDestroyed()).toBe true
 
   describe "::destroy()", ->
     [container, pane1, pane2] = []
diff --git a/spec/window-event-handler-spec.coffee b/spec/window-event-handler-spec.coffee
index d4387f23a..9c9f4a098 100644
--- a/spec/window-event-handler-spec.coffee
+++ b/spec/window-event-handler-spec.coffee
@@ -48,32 +48,6 @@ describe "WindowEventHandler", ->
       window.dispatchEvent(new CustomEvent('window:close'))
       expect(atom.close).toHaveBeenCalled()
 
-  describe "beforeunload event", ->
-    beforeEach ->
-      jasmine.unspy(TextEditor.prototype, "shouldPromptToSave")
-      spyOn(atom, 'destroy')
-      spyOn(ipcRenderer, 'send')
-
-    describe "when pane items are modified", ->
-      editor = null
-      beforeEach ->
-        waitsForPromise -> atom.workspace.open("sample.js").then (o) -> editor = o
-        runs -> editor.insertText("I look different, I feel different.")
-
-      it "prompts the user to save them, and allows the unload to continue if they confirm", ->
-        spyOn(atom.workspace, 'confirmClose').andReturn(true)
-        window.dispatchEvent(new CustomEvent('beforeunload'))
-        expect(atom.workspace.confirmClose).toHaveBeenCalled()
-        expect(ipcRenderer.send).not.toHaveBeenCalledWith('did-cancel-window-unload')
-        expect(atom.destroy).toHaveBeenCalled()
-
-      it "cancels the unload if the user selects cancel", ->
-        spyOn(atom.workspace, 'confirmClose').andReturn(false)
-        window.dispatchEvent(new CustomEvent('beforeunload'))
-        expect(atom.workspace.confirmClose).toHaveBeenCalled()
-        expect(ipcRenderer.send).toHaveBeenCalledWith('did-cancel-window-unload')
-        expect(atom.destroy).not.toHaveBeenCalled()
-
   describe "when a link is clicked", ->
     it "opens the http/https links in an external application", ->
       {shell} = require 'electron'
diff --git a/spec/workspace-spec.js b/spec/workspace-spec.js
index 5d955b452..2626e5dd0 100644
--- a/spec/workspace-spec.js
+++ b/spec/workspace-spec.js
@@ -2394,38 +2394,47 @@ i = /test/; #FIXME\
   })
 
   describe('::saveActivePaneItem()', () => {
-    let editor = null
-    beforeEach(() =>
-      waitsForPromise(() => atom.workspace.open('sample.js').then(o => { editor = o }))
-    )
+    let editor, notificationSpy
+
+    beforeEach(() => {
+      waitsForPromise(() => atom.workspace.open('sample.js').then(o => {
+        editor = o
+      }))
+
+      notificationSpy = jasmine.createSpy('did-add-notification')
+      atom.notifications.onDidAddNotification(notificationSpy)
+    })
 
     describe('when there is an error', () => {
       it('emits a warning notification when the file cannot be saved', () => {
-        let addedSpy
         spyOn(editor, 'save').andCallFake(() => {
           throw new Error("'/some/file' is a directory")
         })
 
-        atom.notifications.onDidAddNotification(addedSpy = jasmine.createSpy())
-        atom.workspace.saveActivePaneItem()
-        expect(addedSpy).toHaveBeenCalled()
-        expect(addedSpy.mostRecentCall.args[0].getType()).toBe('warning')
+        waitsForPromise(() =>
+          atom.workspace.saveActivePaneItem().then(() => {
+            expect(notificationSpy).toHaveBeenCalled()
+            expect(notificationSpy.mostRecentCall.args[0].getType()).toBe('warning')
+            expect(notificationSpy.mostRecentCall.args[0].getMessage()).toContain('Unable to save')
+          })
+        )
       })
 
       it('emits a warning notification when the directory cannot be written to', () => {
-        let addedSpy
         spyOn(editor, 'save').andCallFake(() => {
           throw new Error("ENOTDIR, not a directory '/Some/dir/and-a-file.js'")
         })
 
-        atom.notifications.onDidAddNotification(addedSpy = jasmine.createSpy())
-        atom.workspace.saveActivePaneItem()
-        expect(addedSpy).toHaveBeenCalled()
-        expect(addedSpy.mostRecentCall.args[0].getType()).toBe('warning')
+        waitsForPromise(() =>
+          atom.workspace.saveActivePaneItem().then(() => {
+            expect(notificationSpy).toHaveBeenCalled()
+            expect(notificationSpy.mostRecentCall.args[0].getType()).toBe('warning')
+            expect(notificationSpy.mostRecentCall.args[0].getMessage()).toContain('Unable to save')
+          })
+        )
       })
 
       it('emits a warning notification when the user does not have permission', () => {
-        let addedSpy
         spyOn(editor, 'save').andCallFake(() => {
           const error = new Error("EACCES, permission denied '/Some/dir/and-a-file.js'")
           error.code = 'EACCES'
@@ -2433,10 +2442,13 @@ i = /test/; #FIXME\
           throw error
         })
 
-        atom.notifications.onDidAddNotification(addedSpy = jasmine.createSpy())
-        atom.workspace.saveActivePaneItem()
-        expect(addedSpy).toHaveBeenCalled()
-        expect(addedSpy.mostRecentCall.args[0].getType()).toBe('warning')
+        waitsForPromise(() =>
+          atom.workspace.saveActivePaneItem().then(() => {
+            expect(notificationSpy).toHaveBeenCalled()
+            expect(notificationSpy.mostRecentCall.args[0].getType()).toBe('warning')
+            expect(notificationSpy.mostRecentCall.args[0].getMessage()).toContain('Unable to save')
+          })
+        )
       })
 
       it('emits a warning notification when the operation is not permitted', () => {
@@ -2446,10 +2458,17 @@ i = /test/; #FIXME\
           error.path = '/Some/dir/and-a-file.js'
           throw error
         })
+
+        waitsForPromise(() =>
+          atom.workspace.saveActivePaneItem().then(() => {
+            expect(notificationSpy).toHaveBeenCalled()
+            expect(notificationSpy.mostRecentCall.args[0].getType()).toBe('warning')
+            expect(notificationSpy.mostRecentCall.args[0].getMessage()).toContain('Unable to save')
+          })
+        )
       })
 
       it('emits a warning notification when the file is already open by another app', () => {
-        let addedSpy
         spyOn(editor, 'save').andCallFake(() => {
           const error = new Error("EBUSY, resource busy or locked '/Some/dir/and-a-file.js'")
           error.code = 'EBUSY'
@@ -2457,17 +2476,16 @@ i = /test/; #FIXME\
           throw error
         })
 
-        atom.notifications.onDidAddNotification(addedSpy = jasmine.createSpy())
-        atom.workspace.saveActivePaneItem()
-        expect(addedSpy).toHaveBeenCalled()
-
-        const notificaiton = addedSpy.mostRecentCall.args[0]
-        expect(notificaiton.getType()).toBe('warning')
-        expect(notificaiton.getMessage()).toContain('Unable to save')
+        waitsForPromise(() =>
+          atom.workspace.saveActivePaneItem().then(() => {
+            expect(notificationSpy).toHaveBeenCalled()
+            expect(notificationSpy.mostRecentCall.args[0].getType()).toBe('warning')
+            expect(notificationSpy.mostRecentCall.args[0].getMessage()).toContain('Unable to save')
+          })
+        )
       })
 
       it('emits a warning notification when the file system is read-only', () => {
-        let addedSpy
         spyOn(editor, 'save').andCallFake(() => {
           const error = new Error("EROFS, read-only file system '/Some/dir/and-a-file.js'")
           error.code = 'EROFS'
@@ -2475,13 +2493,13 @@ i = /test/; #FIXME\
           throw error
         })
 
-        atom.notifications.onDidAddNotification(addedSpy = jasmine.createSpy())
-        atom.workspace.saveActivePaneItem()
-        expect(addedSpy).toHaveBeenCalled()
-
-        const notification = addedSpy.mostRecentCall.args[0]
-        expect(notification.getType()).toBe('warning')
-        expect(notification.getMessage()).toContain('Unable to save')
+        waitsForPromise(() =>
+          atom.workspace.saveActivePaneItem().then(() => {
+            expect(notificationSpy).toHaveBeenCalled()
+            expect(notificationSpy.mostRecentCall.args[0].getType()).toBe('warning')
+            expect(notificationSpy.mostRecentCall.args[0].getMessage()).toContain('Unable to save')
+          })
+        )
       })
 
       it('emits a warning notification when the file cannot be saved', () => {
@@ -2489,8 +2507,9 @@ i = /test/; #FIXME\
           throw new Error('no one knows')
         })
 
-        const save = () => atom.workspace.saveActivePaneItem()
-        expect(save).toThrow()
+        waitsForPromise({shouldReject: true}, () =>
+          atom.workspace.saveActivePaneItem()
+        )
       })
     })
   })
diff --git a/src/application-delegate.coffee b/src/application-delegate.coffee
index e69efa458..fdb7119e1 100644
--- a/src/application-delegate.coffee
+++ b/src/application-delegate.coffee
@@ -232,19 +232,14 @@ class ApplicationDelegate
     new Disposable ->
       ipcRenderer.removeListener('context-command', outerCallback)
 
-  onSaveWindowStateRequest: (callback) ->
+  onDidRequestUnload: (callback) ->
     outerCallback = (event, message) ->
-      callback(event)
+      callback(event).then (shouldUnload) ->
+        ipcRenderer.send('did-prepare-to-unload', shouldUnload)
 
-    ipcRenderer.on('save-window-state', outerCallback)
+    ipcRenderer.on('prepare-to-unload', outerCallback)
     new Disposable ->
-      ipcRenderer.removeListener('save-window-state', outerCallback)
-
-  didSaveWindowState: ->
-    ipcRenderer.send('did-save-window-state')
-
-  didCancelWindowUnload: ->
-    ipcRenderer.send('did-cancel-window-unload')
+      ipcRenderer.removeListener('prepare-to-unload', outerCallback)
 
   onDidChangeHistoryManager: (callback) ->
     outerCallback = (event, message) ->
diff --git a/src/atom-environment.coffee b/src/atom-environment.coffee
index 9f5896071..f35ed39d8 100644
--- a/src/atom-environment.coffee
+++ b/src/atom-environment.coffee
@@ -694,9 +694,14 @@ class AtomEnvironment extends Model
         @disposables.add(@applicationDelegate.onDidOpenLocations(@openLocations.bind(this)))
         @disposables.add(@applicationDelegate.onApplicationMenuCommand(@dispatchApplicationMenuCommand.bind(this)))
         @disposables.add(@applicationDelegate.onContextMenuCommand(@dispatchContextMenuCommand.bind(this)))
-        @disposables.add @applicationDelegate.onSaveWindowStateRequest =>
-          callback = => @applicationDelegate.didSaveWindowState()
-          @saveState({isUnloading: true}).catch(callback).then(callback)
+        @disposables.add @applicationDelegate.onDidRequestUnload =>
+          @saveState({isUnloading: true})
+            .catch(console.error)
+            .then =>
+              @workspace?.confirmClose({
+                windowCloseRequested: true,
+                projectHasPaths: @project.getPaths().length > 0
+              })
 
         @listenForUpdates()
 
diff --git a/src/main-process/atom-application.coffee b/src/main-process/atom-application.coffee
index 302257fb1..944f2783c 100644
--- a/src/main-process/atom-application.coffee
+++ b/src/main-process/atom-application.coffee
@@ -270,7 +270,7 @@ class AtomApplication
       unless @quitting
         event.preventDefault()
         @quitting = true
-        Promise.all(@windows.map((window) -> window.saveState())).then(-> app.quit())
+        Promise.all(@windows.map((window) -> window.prepareToUnload())).then(-> app.quit())
 
     @disposable.add ipcHelpers.on app, 'will-quit', =>
       @killAllProcesses()
@@ -373,11 +373,6 @@ class AtomApplication
     @disposable.add ipcHelpers.respondTo 'set-temporary-window-state', (win, state) ->
       win.temporaryState = state
 
-    @disposable.add ipcHelpers.on ipcMain, 'did-cancel-window-unload', =>
-      @quitting = false
-      for window in @windows
-        window.didCancelWindowUnload()
-
     clipboard = require '../safe-clipboard'
     @disposable.add ipcHelpers.on ipcMain, 'write-text-to-selection-clipboard', (event, selectedText) ->
       clipboard.writeText(selectedText, 'selection')
diff --git a/src/main-process/atom-window.coffee b/src/main-process/atom-window.coffee
index d920fa5d2..3547f3032 100644
--- a/src/main-process/atom-window.coffee
+++ b/src/main-process/atom-window.coffee
@@ -147,7 +147,8 @@ class AtomWindow
         event.preventDefault()
         @unloading = true
         @atomApplication.saveState(false)
-        @saveState().then(=> @close())
+        @prepareToUnload().then (result) =>
+          @close() if result
 
     @browserWindow.on 'closed', =>
       @fileRecoveryService.didCloseWindow(this)
@@ -191,21 +192,19 @@ class AtomWindow
       @browserWindow.on 'blur', =>
         @browserWindow.focusOnWebView()
 
-  didCancelWindowUnload: ->
-    @unloading = false
-
-  saveState: ->
+  prepareToUnload: ->
     if @isSpecWindow()
       return Promise.resolve()
-
-    @lastSaveStatePromise = new Promise (resolve) =>
-      callback = (event) =>
+    @lastPrepareToUnloadPromise = new Promise (resolve) =>
+      callback = (event, result) =>
         if BrowserWindow.fromWebContents(event.sender) is @browserWindow
-          ipcMain.removeListener('did-save-window-state', callback)
-          resolve()
-      ipcMain.on('did-save-window-state', callback)
-      @browserWindow.webContents.send('save-window-state')
-    @lastSaveStatePromise
+          ipcMain.removeListener('did-prepare-to-unload', callback)
+          unless result
+            @unloading = false
+            @atomApplication.quitting = false
+          resolve(result)
+      ipcMain.on('did-prepare-to-unload', callback)
+      @browserWindow.webContents.send('prepare-to-unload')
 
   openPath: (pathToOpen, initialLine, initialColumn) ->
     @openLocations([{pathToOpen, initialLine, initialColumn}])
@@ -287,7 +286,8 @@ class AtomWindow
 
   reload: ->
     @loadedPromise = new Promise((@resolveLoadedPromise) =>)
-    @saveState().then => @browserWindow.reload()
+    @prepareToUnload().then (result) =>
+      @browserWindow.reload() if result
     @loadedPromise
 
   showSaveDialog: (params) ->
diff --git a/src/pane-container.js b/src/pane-container.js
index 88922c000..0a6fc2694 100644
--- a/src/pane-container.js
+++ b/src/pane-container.js
@@ -172,18 +172,13 @@ class PaneContainer {
   }
 
   confirmClose (options) {
-    let allSaved = true
-
-    for (let pane of this.getPanes()) {
-      for (let item of pane.getItems()) {
-        if (!pane.promptToSaveItem(item, options)) {
-          allSaved = false
-          break
-        }
+    const promises = []
+    for (const pane of this.getPanes()) {
+      for (const item of pane.getItems()) {
+        promises.push(pane.promptToSaveItem(item, options))
       }
     }
-
-    return allSaved
+    return Promise.all(promises).then((results) => !results.includes(false))
   }
 
   activateNextPane () {
diff --git a/src/pane.coffee b/src/pane.coffee
index 31ee92f77..ed2b3a639 100644
--- a/src/pane.coffee
+++ b/src/pane.coffee
@@ -602,39 +602,47 @@ class Pane
   # * `force` (optional) {Boolean} Destroy the item without prompting to save
   #    it, even if the item's `isPermanentDockItem` method returns true.
   #
-  # Returns a {Boolean} indicating whether or not the item was destroyed.
+  # Returns a {Promise} that resolves with a {Boolean} indicating whether or not
+  # the item was destroyed.
   destroyItem: (item, force) ->
     index = @items.indexOf(item)
     if index isnt -1
       return false if not force and @getContainer()?.getLocation() isnt 'center' and item.isPermanentDockItem?()
       @emitter.emit 'will-destroy-item', {item, index}
       @container?.willDestroyPaneItem({item, index, pane: this})
-      if force or @promptToSaveItem(item)
+      if force or not item?.shouldPromptToSave?()
         @removeItem(item, false)
         item.destroy?()
-        true
       else
-        false
+        @promptToSaveItem(item).then (result) =>
+          if result
+            @removeItem(item, false)
+            item.destroy?()
+          result
 
   # Public: Destroy all items.
   destroyItems: ->
-    @destroyItem(item) for item in @getItems()
-    return
+    Promise.all(
+      @getItems().map(@destroyItem.bind(this))
+    )
 
   # Public: Destroy all items except for the active item.
   destroyInactiveItems: ->
-    @destroyItem(item) for item in @getItems() when item isnt @activeItem
-    return
+    Promise.all(
+      @getItems()
+        .filter((item) => item isnt @activeItem)
+        .map(@destroyItem.bind(this))
+    )
 
   promptToSaveItem: (item, options={}) ->
-    return true unless item.shouldPromptToSave?(options)
+    return Promise.resolve(true) unless item.shouldPromptToSave?(options)
 
     if typeof item.getURI is 'function'
       uri = item.getURI()
     else if typeof item.getUri is 'function'
       uri = item.getUri()
     else
-      return true
+      return Promise.resolve(true)
 
     saveDialog = (saveButtonText, saveFn, message) =>
       chosen = @applicationDelegate.confirm
@@ -642,15 +650,21 @@ class Pane
         detailedMessage: "Your changes will be lost if you close this item without saving."
         buttons: [saveButtonText, "Cancel", "Don't Save"]
       switch chosen
-        when 0 then saveFn(item, saveError)
-        when 1 then false
-        when 2 then true
+        when 0
+          new Promise (resolve) ->
+            saveFn item, (error) ->
+              console.log 'error', error
+              saveError(error).then(resolve)
+        when 1
+          Promise.resolve(false)
+        when 2
+          Promise.resolve(true)
 
     saveError = (error) =>
       if error
         saveDialog("Save as", @saveItemAs, "'#{item.getTitle?() ? uri}' could not be saved.\nError: #{@getMessageForErrorCode(error.code)}")
       else
-        true
+        Promise.resolve(true)
 
     saveDialog("Save", @saveItem, "'#{item.getTitle?() ? uri}' has changes, do you want to save them?")
 
@@ -663,6 +677,8 @@ class Pane
   #
   # * `nextAction` (optional) {Function} which will be called after the item is
   #   successfully saved.
+  #
+  # Returns a {Promise} that resolves when the save is complete
   saveActiveItemAs: (nextAction) ->
     @saveItemAs(@getActiveItem(), nextAction)
 
@@ -673,6 +689,8 @@ class Pane
   #   after the item is successfully saved, or with the error if it failed.
   #   The return value will be that of `nextAction` or `undefined` if it was not
   #   provided
+  #
+  # Returns a {Promise} that resolves when the save is complete
   saveItem: (item, nextAction) =>
     if typeof item?.getURI is 'function'
       itemURI = item.getURI()
@@ -680,14 +698,16 @@ class Pane
       itemURI = item.getUri()
 
     if itemURI?
-      try
-        item.save?()
+      if item.save?
+        promisify -> item.save()
+          .then -> nextAction?()
+          .catch (error) =>
+            if nextAction
+              nextAction(error)
+            else
+              @handleSaveError(error, item)
+      else
         nextAction?()
-      catch error
-        if nextAction
-          nextAction(error)
-        else
-          @handleSaveError(error, item)
     else
       @saveItemAs(item, nextAction)
 
@@ -706,14 +726,13 @@ class Pane
     saveOptions.defaultPath ?= item.getPath()
     newItemPath = @applicationDelegate.showSaveDialog(saveOptions)
     if newItemPath
-      try
-        item.saveAs(newItemPath)
-        nextAction?()
-      catch error
-        if nextAction
-          nextAction(error)
-        else
-          @handleSaveError(error, item)
+      promisify -> item.saveAs(newItemPath)
+        .then -> nextAction?()
+        .catch (error) =>
+          if nextAction?
+            nextAction(error)
+          else
+            @handleSaveError(error, item)
 
   # Public: Save all items.
   saveItems: ->
@@ -909,13 +928,13 @@ class Pane
     bottommostSibling = @findBottommostSibling()
     if bottommostSibling is this then @splitDown() else bottommostSibling
 
+  # Private: Close the pane unless the user cancels the action via a dialog.
+  #
+  # Returns a {Promise} that resolves once the pane is either closed, or the
+  # closing has been cancelled.
   close: ->
-    @destroy() if @confirmClose()
-
-  confirmClose: ->
-    for item in @getItems()
-      return false unless @promptToSaveItem(item)
-    true
+    Promise.all(@getItems().map(@promptToSaveItem.bind(this))).then (results) =>
+      @destroy() unless results.includes(false)
 
   handleSaveError: (error, item) ->
     itemPath = error.path ? item?.getPath?()
@@ -948,3 +967,9 @@ class Pane
       when 'EROFS' then 'Read-only file system'
       when 'ESPIPE' then 'Invalid seek'
       when 'ETIMEDOUT' then 'Connection timed out'
+
+promisify = (callback) ->
+  try
+    Promise.resolve(callback())
+  catch error
+    Promise.reject(error)
\ No newline at end of file
diff --git a/src/window-event-handler.coffee b/src/window-event-handler.coffee
index aac0f0ba5..6a277b612 100644
--- a/src/window-event-handler.coffee
+++ b/src/window-event-handler.coffee
@@ -147,19 +147,12 @@ class WindowEventHandler
     @document.body.classList.remove("fullscreen")
 
   handleWindowBeforeunload: (event) =>
-    projectHasPaths = @atomEnvironment.project.getPaths().length > 0
-    confirmed = @atomEnvironment.workspace?.confirmClose(windowCloseRequested: true, projectHasPaths: projectHasPaths)
-    if confirmed and not @reloadRequested and not @atomEnvironment.inSpecMode() and @atomEnvironment.getCurrentWindow().isWebViewFocused()
+    if not @reloadRequested and not @atomEnvironment.inSpecMode() and @atomEnvironment.getCurrentWindow().isWebViewFocused()
       @atomEnvironment.hide()
     @reloadRequested = false
-
     @atomEnvironment.storeWindowDimensions()
-    if confirmed
-      @atomEnvironment.unloadEditorWindow()
-      @atomEnvironment.destroy()
-    else
-      @applicationDelegate.didCancelWindowUnload()
-      event.returnValue = false
+    @atomEnvironment.unloadEditorWindow()
+    @atomEnvironment.destroy()
 
   handleWindowToggleFullScreen: =>
     @atomEnvironment.toggleFullScreen()
diff --git a/src/workspace.js b/src/workspace.js
index c886167c8..11bc9ba6b 100644
--- a/src/workspace.js
+++ b/src/workspace.js
@@ -1299,9 +1299,9 @@ module.exports = class Workspace extends Model {
   }
 
   confirmClose (options) {
-    return this.getPaneContainers()
-      .map(container => container.confirmClose(options))
-      .every(saved => saved)
+    return Promise.all(this.getPaneContainers().map(container =>
+      container.confirmClose(options)
+    )).then((results) => !results.includes(false))
   }
 
   // Save the active pane item.
@@ -1311,7 +1311,7 @@ module.exports = class Workspace extends Model {
   // {::saveActivePaneItemAs} # will be called instead. This method does nothing
   // if the active item does not implement a `.save` method.
   saveActivePaneItem () {
-    this.getCenter().getActivePane().saveActiveItem()
+    return this.getCenter().getActivePane().saveActiveItem()
   }
 
   // Prompt the user for a path and save the active pane item to it.