diff --git a/spec/app/selection-spec.coffee b/spec/app/selection-spec.coffee
index 8caa38c11..b8932f464 100644
--- a/spec/app/selection-spec.coffee
+++ b/spec/app/selection-spec.coffee
@@ -274,6 +274,24 @@ describe "Selection", ->
         expect(editor.buffer.lineForRow(2)).toBe "  if (items.length <= 1) return items;"
         expect(selection.getBufferRange()).toEqual [[0, 1], [3, 15 - tabLength]]
 
+  describe ".toggleLineComments()", ->
+    it "toggles comments on the selected lines", ->
+      selection.setBufferRange([[4, 5], [7, 5]])
+      selection.toggleLineComments()
+
+      expect(buffer.lineForRow(4)).toBe "//    while(items.length > 0) {"
+      expect(buffer.lineForRow(5)).toBe "//      current = items.shift();"
+      expect(buffer.lineForRow(6)).toBe "//      current < pivot ? left.push(current) : right.push(current);"
+      expect(buffer.lineForRow(7)).toBe "//    }"
+
+      expect(selection.getBufferRange()).toEqual [[4, 7], [7, 7]]
+
+      selection.toggleLineComments()
+      expect(buffer.lineForRow(4)).toBe "    while(items.length > 0) {"
+      expect(buffer.lineForRow(5)).toBe "      current = items.shift();"
+      expect(buffer.lineForRow(6)).toBe "      current < pivot ? left.push(current) : right.push(current);"
+      expect(buffer.lineForRow(7)).toBe "    }"
+
   describe "when the selection ends on the begining of a fold line", ->
     beforeEach ->
       editor.createFold(2,4)
diff --git a/src/app/composite-selection.coffee b/src/app/composite-selection.coffee
index 5a6887b45..7ca846203 100644
--- a/src/app/composite-selection.coffee
+++ b/src/app/composite-selection.coffee
@@ -113,6 +113,9 @@ class CompositeSeleciton
   deleteToEndOfWord: ->
     @mutateSelectedText (selection) -> selection.deleteToEndOfWord()
 
+  toggleLineComments: ->
+    @mutateSelectedText (selection) -> selection.toggleLineComments()
+
   selectToScreenPosition: (position) ->
     @getLastSelection().selectToScreenPosition(position)
 
diff --git a/src/app/editor.coffee b/src/app/editor.coffee
index ce2f02ee8..1f8a329bf 100644
--- a/src/app/editor.coffee
+++ b/src/app/editor.coffee
@@ -38,7 +38,6 @@ class Editor extends View
   cursor: null
   selection: null
   buffer: null
-  highlighter: null
   renderer: null
   autoIndent: null
   lineCache: null
@@ -146,6 +145,7 @@ class Editor extends View
       'select-to-end-of-word': @selectToEndOfWord
       'select-to-beginning-of-word': @selectToBeginningOfWord
       'select-all': @selectAll
+      'toggle-line-comments': @toggleLineCommentsInSelection
 
     for name, method of editorBindings
       do (name, method) =>
@@ -820,6 +820,12 @@ class Editor extends View
   logLines: (start, end) ->
     @renderer.logLines(start, end)
 
+  toggleLineCommentsInSelection: ->
+    @compositeSelection.toggleLineComments()
+
+  toggleLineCommentsInRange: (range) ->
+    @renderer.toggleLineCommentsInRange(range)
+
   logRenderedLines: ->
     @visibleLines.find('.line').each (n) ->
       console.log n, $(this).text()
diff --git a/src/app/keymaps/editor.coffee b/src/app/keymaps/editor.coffee
index be5805138..783de3ec8 100644
--- a/src/app/keymaps/editor.coffee
+++ b/src/app/keymaps/editor.coffee
@@ -30,3 +30,4 @@ window.keymap.bindKeys '.editor',
   'meta-}': 'show-next-buffer'
   'meta-+': 'increase-font-size'
   'meta--': 'decrease-font-size'
+  'meta-/': 'toggle-line-comments'
diff --git a/src/app/renderer.coffee b/src/app/renderer.coffee
index 2de0c9f10..f23f17a88 100644
--- a/src/app/renderer.coffee
+++ b/src/app/renderer.coffee
@@ -8,7 +8,7 @@ Range = require 'range'
 Fold = require 'fold'
 ScreenLine = require 'screen-line'
 Token = require 'token'
-foldPlaceholderLength = 3
+LineCommenter = require 'line-commenter'
 
 module.exports =
 class Renderer
@@ -16,13 +16,14 @@ class Renderer
   lineMap: null
   highlighter: null
   activeFolds: null
+  lineCommenter: null
   foldsById: null
   lastHighlighterChangeEvent: null
-  foldPlaceholderLength: 3
 
   constructor: (@buffer, options={}) ->
     @id = @constructor.idCounter++
     @highlighter = new Highlighter(@buffer, options.tabText ? '  ')
+    @lineCommenter = new LineCommenter(@highlighter)
     @foldSuggester = new FoldSuggester(@highlighter)
     @maxLineLength = options.maxLineLength ? Infinity
     @activeFolds = {}
@@ -246,4 +247,8 @@ class Renderer
   logLines: (start, end) ->
     @lineMap.logLines(start, end)
 
+  toggleLineCommentsInRange: (range) ->
+    console.log range.inspect()
+    @lineCommenter.toggleLineCommentsInRange(range)
+
 _.extend Renderer.prototype, EventEmitter
diff --git a/src/app/selection.coffee b/src/app/selection.coffee
index a02f34603..f460fe24b 100644
--- a/src/app/selection.coffee
+++ b/src/app/selection.coffee
@@ -84,6 +84,7 @@ class Selection extends View
       new Range(@cursor.getScreenPosition(), @cursor.getScreenPosition())
 
   setScreenRange: (range, {reverse}={}) ->
+    range = Range.fromObject(range)
     { start, end } = range
     [start, end] = [end, start] if reverse
 
@@ -125,6 +126,10 @@ class Selection extends View
       if leadingTabRegex.test buffer.lineForRow(row)
         buffer.delete [[row, 0], [row, @editor.tabText.length]]
 
+  toggleLineComments: ->
+    @modifySelection =>
+      @editor.toggleLineCommentsInRange(@getBufferRange())
+
   autoIndentText: (text) ->
     if @editor.autoIndent
       mode = @editor.getCurrentMode()