diff --git a/spec/panel-container-element-spec.coffee b/spec/panel-container-element-spec.coffee
index 3dd6b2b18..12e28e04d 100644
--- a/spec/panel-container-element-spec.coffee
+++ b/spec/panel-container-element-spec.coffee
@@ -49,6 +49,7 @@ describe "PanelContainerElement", ->
       panel1 = new Panel({viewRegistry, item: new TestPanelContainerItem(), location: 'left'})
       container.addPanel(panel1)
       expect(element.childNodes.length).toBe 1
+      expect(element.childNodes[0].getAttribute('location')).toBe 'left'
 
       expect(element.childNodes[0].tagName).toBe 'ATOM-PANEL'
 
@@ -56,8 +57,34 @@ describe "PanelContainerElement", ->
       container.addPanel(panel2)
       expect(element.childNodes.length).toBe 2
 
+      expect(panel1.getView().style.display).not.toBe 'none'
+      expect(panel2.getView().style.display).not.toBe 'none'
+
       panel1.destroy()
       expect(element.childNodes.length).toBe 1
 
       panel2.destroy()
       expect(element.childNodes.length).toBe 0
+
+  describe "when the container is modal", ->
+    beforeEach ->
+      container = new PanelContainer({viewRegistry, location: 'modal'})
+      element = container.getView()
+      jasmineContent.appendChild(element)
+
+    it "allows only one panel to be visible at a time", ->
+      panel1 = new Panel({viewRegistry, item: new TestPanelContainerItem()})
+      container.addPanel(panel1)
+
+      expect(panel1.getView().style.display).not.toBe 'none'
+
+      panel2 = new Panel({viewRegistry, item: new TestPanelContainerItem()})
+      container.addPanel(panel2)
+
+      expect(panel1.getView().style.display).toBe 'none'
+      expect(panel2.getView().style.display).not.toBe 'none'
+
+      panel1.show()
+
+      expect(panel1.getView().style.display).not.toBe 'none'
+      expect(panel2.getView().style.display).toBe 'none'
diff --git a/spec/panel-element-spec.coffee b/spec/panel-element-spec.coffee
index 7cf7f8d8b..c283e158d 100644
--- a/spec/panel-element-spec.coffee
+++ b/spec/panel-element-spec.coffee
@@ -54,3 +54,12 @@ describe "PanelElement", ->
 
       panel.show()
       expect(element.style.display).not.toBe 'none'
+
+  describe "when a class name is specified", ->
+    it 'initially renders panel created with visibile: false', ->
+      panel = new Panel({viewRegistry, className: 'some classes', item: new TestPanelItem})
+      element = panel.getView()
+      jasmineContent.appendChild(element)
+
+      expect(element).toHaveClass 'some'
+      expect(element).toHaveClass 'classes'
diff --git a/spec/workspace-spec.coffee b/spec/workspace-spec.coffee
index e844acecd..edd954acc 100644
--- a/spec/workspace-spec.coffee
+++ b/spec/workspace-spec.coffee
@@ -492,3 +492,12 @@ describe "Workspace", ->
 
         expect(panel).toBeDefined()
         expect(addPanelSpy).toHaveBeenCalledWith({panel, index: 0})
+
+    describe '::addModalPanel(model)', ->
+      it 'adds a panel to the correct panel container', ->
+        atom.workspace.panelContainers.modal.onDidAddPanel addPanelSpy = jasmine.createSpy()
+        panel = atom.workspace.addModalPanel(item: new TestPanel())
+
+        expect(panel).toBeDefined()
+        expect(addPanelSpy).toHaveBeenCalledWith({panel, index: 0})
+        expect(panel.getClassName()).toBe 'overlay from-top' # the default
diff --git a/spec/workspace-view-spec.coffee b/spec/workspace-view-spec.coffee
index ff0eff660..4b40b20c4 100644
--- a/spec/workspace-view-spec.coffee
+++ b/spec/workspace-view-spec.coffee
@@ -286,3 +286,6 @@ describe "WorkspaceView", ->
       bottomContainer = workspaceElement.querySelector('atom-panel-container[location="bottom"]')
       expect(topContainer.nextSibling).toBe workspaceElement.paneContainer
       expect(bottomContainer.previousSibling).toBe workspaceElement.paneContainer
+
+      modalContainer = workspaceElement.querySelector('atom-panel-container[location="modal"]')
+      expect(modalContainer.parentNode).toBe workspaceElement
diff --git a/src/panel-container-element.coffee b/src/panel-container-element.coffee
index fb5c6684e..d162686cf 100644
--- a/src/panel-container-element.coffee
+++ b/src/panel-container-element.coffee
@@ -14,11 +14,18 @@ class PanelContainerElement extends HTMLElement
     @setAttribute('location', @model.getLocation())
 
   panelAdded: ({panel, index}) ->
+    panelElement = panel.getView()
+    panelElement.setAttribute('location', @model.getLocation())
     if index >= @childNodes.length
-      @appendChild(panel.getView())
+      @appendChild(panelElement)
     else
       referenceItem = @childNodes[index + 1]
-      @insertBefore(panel.getView(), referenceItem)
+      @insertBefore(panelElement, referenceItem)
+
+    if @model.isModal()
+      @hideAllPanelsExcept(panel)
+      @subscriptions.add panel.onDidChangeVisible (visible) =>
+        @hideAllPanelsExcept(panel) if visible
 
   panelRemoved: ({panel, index}) ->
     @removeChild(@childNodes[index])
@@ -27,4 +34,9 @@ class PanelContainerElement extends HTMLElement
     @subscriptions.dispose()
     @parentNode?.removeChild(this)
 
+  hideAllPanelsExcept: (excludedPanel) ->
+    for panel in @model.getPanels()
+      panel.hide() unless panel is excludedPanel
+    return
+
 module.exports = PanelContainerElement = document.registerElement 'atom-panel-container', prototype: PanelContainerElement.prototype
diff --git a/src/panel-container.coffee b/src/panel-container.coffee
index 4bf7e30ba..24d48eac1 100644
--- a/src/panel-container.coffee
+++ b/src/panel-container.coffee
@@ -34,6 +34,8 @@ class PanelContainer
 
   getLocation: -> @location
 
+  isModal: -> @location is 'modal'
+
   getPanels: -> @panels
 
   addPanel: (panel) ->
diff --git a/src/panel-element.coffee b/src/panel-element.coffee
index 87d0fdafc..eec1d91b5 100644
--- a/src/panel-element.coffee
+++ b/src/panel-element.coffee
@@ -12,6 +12,7 @@ class PanelElement extends HTMLElement
     @appendChild(view)
     callAttachHooks(view) # for backward compatibility with SpacePen views
 
+    @classList.add(@model.getClassName().split(' ')...) if @model.getClassName()?
     @subscriptions.add @model.onDidChangeVisible(@visibleChanged.bind(this))
     @subscriptions.add @model.onDidDestroy(@destroyed.bind(this))
 
diff --git a/src/panel.coffee b/src/panel.coffee
index 048d6840e..365e4ad5e 100644
--- a/src/panel.coffee
+++ b/src/panel.coffee
@@ -14,7 +14,7 @@ class Panel
   Section: Construction and Destruction
   ###
 
-  constructor: ({@viewRegistry, @item, @visible, @priority}) ->
+  constructor: ({@viewRegistry, @item, @visible, @priority, @className}) ->
     @emitter = new Emitter
     @visible ?= true
     @priority ?= 100
@@ -22,6 +22,7 @@ class Panel
   # Public: Destroy and remove this panel from the UI.
   destroy: ->
     @emitter.emit 'did-destroy', this
+    @emitter.dispose()
 
   ###
   Section: Event Subscription
@@ -62,6 +63,8 @@ class Panel
   # Public: Returns a {Number} indicating this panel's priority.
   getPriority: -> @priority
 
+  getClassName: -> @className
+
   # Public: Returns a {Boolean} true when the panel is visible.
   isVisible: -> @visible
 
diff --git a/src/workspace-element.coffee b/src/workspace-element.coffee
index 73a9438af..3994ccfe9 100644
--- a/src/workspace-element.coffee
+++ b/src/workspace-element.coffee
@@ -77,6 +77,7 @@ class WorkspaceElement extends HTMLElement
       left: @model.panelContainers.left.getView()
       right: @model.panelContainers.right.getView()
       bottom: @model.panelContainers.bottom.getView()
+      modal: @model.panelContainers.modal.getView()
 
     @horizontalAxis.insertBefore(@panelContainers.left, @verticalAxis)
     @horizontalAxis.appendChild(@panelContainers.right)
@@ -84,6 +85,8 @@ class WorkspaceElement extends HTMLElement
     @verticalAxis.insertBefore(@panelContainers.top, @paneContainer)
     @verticalAxis.appendChild(@panelContainers.bottom)
 
+    @appendChild(@panelContainers.modal)
+
     @__spacePenView.setModel(@model)
 
   setTextEditorFontSize: (fontSize) ->
diff --git a/src/workspace.coffee b/src/workspace.coffee
index e4fa0ffb9..d88f9196a 100644
--- a/src/workspace.coffee
+++ b/src/workspace.coffee
@@ -54,6 +54,7 @@ class Workspace extends Model
       left: new PanelContainer({viewRegistry, location: 'left'})
       right: new PanelContainer({viewRegistry, location: 'right'})
       bottom: new PanelContainer({viewRegistry, location: 'bottom'})
+      modal: new PanelContainer({viewRegistry, location: 'modal'})
 
     @subscribeToActiveItem()
 
@@ -660,6 +661,23 @@ class Workspace extends Model
   addTopPanel: (options) ->
     @addPanel('top', options)
 
+  # Essential: Adds a panel item as a modal dialog.
+  #
+  # * `options` {Object}
+  #   * `item` Your panel content. It can be DOM element, a jQuery element, or
+  #     a model with a view registered via {ViewRegistry::addViewProvider}. We recommend the
+  #     latter. See {ViewRegistry::addViewProvider} for more information.
+  #   * `visible` (optional) {Boolean} false if you want the panel to initially be hidden
+  #     (default: true)
+  #   * `priority` (optional) {Number} Determines stacking order. Lower priority items are
+  #     forced closer to the edges of the window. (default: 100)
+  #
+  # Returns a {Panel}
+  addModalPanel: (options={}) ->
+    # TODO: remove these default classes. They are to supoprt existing themes.
+    options.className ?= 'overlay from-top'
+    @addPanel('modal', options)
+
   addPanel: (location, options) ->
     options ?= {}
     options.viewRegistry = atom.views
diff --git a/static/overlay.less b/static/overlay.less
index ee6f983ac..6bcd85ea7 100644
--- a/static/overlay.less
+++ b/static/overlay.less
@@ -1,6 +1,7 @@
 @import "ui-variables";
 
-.overlay {
+.overlay,
+atom-panel[location="modal"] {
   position: absolute;
   left: 50%;
   width: 500px;
@@ -8,7 +9,9 @@
   z-index: 9999;
   box-sizing: border-box;
 
-  background-color: #fff;
+  color: @text-color;
+  background-color: @overlay-background-color;
+
   padding: 10px;
 
   h1 {
@@ -21,30 +24,32 @@
   h2 {
     font-size: 1.3em;
   }
+
+  atom-text-editor.mini {
+    margin-bottom: 10px;
+  }
+
+  .message {
+    padding-top: 5px;
+    font-size: 11px;
+  }
+
+  &.mini {
+    width: 200px;
+    margin-left: -100px;
+    font-size: 12px;
+  }
 }
 
-.overlay atom-text-editor.mini {
-  margin-bottom: 10px;
-}
-
-.overlay .message {
-  padding-top: 5px;
-  font-size: 11px;
-}
-
-.overlay.mini {
-  width: 200px;
-  margin-left: -100px;
-  font-size: 12px;
-}
-
-.overlay.from-top {
+.overlay.from-top, // TODO: Remove the .from-* classes
+atom-panel[location="modal"] {
   top: 0;
   border-top: none;
   border-top-left-radius: 0;
   border-top-right-radius: 0;
 }
 
+// TODO: Remove these!
 .overlay.from-bottom {
   bottom: 0;
   border-bottom: none;