diff --git a/exports/nylas-component-kit.coffee b/exports/nylas-component-kit.coffee
index 16a03ce7f..67caa8066 100644
--- a/exports/nylas-component-kit.coffee
+++ b/exports/nylas-component-kit.coffee
@@ -33,6 +33,7 @@ class NylasComponentKit
 
   @loadFrom "MailLabel", "mail-label"
   @loadFrom "LabelColorizer", "mail-label"
+  @load "MailImportantIcon", 'mail-important-icon'
 
   @loadFrom "FormItem", "generated-form"
   @loadFrom "GeneratedForm", "generated-form"
diff --git a/internal_packages/message-list/lib/message-list.cjsx b/internal_packages/message-list/lib/message-list.cjsx
index 3f2c5c93d..cae8fbd1b 100755
--- a/internal_packages/message-list/lib/message-list.cjsx
+++ b/internal_packages/message-list/lib/message-list.cjsx
@@ -20,6 +20,7 @@ MessageItemContainer = require './message-item-container'
  RetinaImg,
  InjectedComponentSet,
  MailLabel,
+ MailImportantIcon,
  InjectedComponent} = require('nylas-component-kit')
 
 class MessageListScrollTooltip extends React.Component
@@ -218,13 +219,18 @@ class MessageList extends React.Component
     </div>
 
   _renderSubject: ->
+    subject = @state.currentThread?.subject
+    subject = "(No Subject)" if not subject or subject.length is 0
+
     <div className="message-subject-wrap">
-      <span className="message-subject">{@state.currentThread?.subject}</span>
+      <MailImportantIcon thread={@state.currentThread} />
+      <span className="message-subject">{subject}</span>
       {@_renderLabels()}
     </div>
 
   _renderLabels: =>
     labels = @state.currentThread.sortedLabels()
+    labels = _.reject labels, (l) -> l.name is 'important'
     labels.map (label) =>
       <MailLabel label={label} key={label.id} onRemove={ => @_onRemoveLabel(label) }/>
 
diff --git a/internal_packages/message-list/stylesheets/message-list.less b/internal_packages/message-list/stylesheets/message-list.less
index f7ba6a232..db7770840 100644
--- a/internal_packages/message-list/stylesheets/message-list.less
+++ b/internal_packages/message-list/stylesheets/message-list.less
@@ -68,6 +68,7 @@
   display: flex;
   flex-direction: column;
   position: relative;
+  background: @background-secondary;
 
   width: 100%;
   height: 100%;
@@ -83,6 +84,10 @@
     -webkit-user-select: text;
     line-height: @font-size-large * 1.8;
   }
+  .mail-important-icon {
+    margin-right:@spacing-half;
+    margin-bottom:2px;
+  }
   .message-subject {
     font-size: @font-size-large;
     color: @text-color;
@@ -109,7 +114,6 @@
     flex: 1;
     opacity:0;
     transition: opacity 0s;
-    background: @background-secondary;
   }
   .messages-wrap.ready {
     opacity:1;
diff --git a/internal_packages/preferences/lib/tabs/preferences-general.cjsx b/internal_packages/preferences/lib/tabs/preferences-general.cjsx
index da2301e17..a527c34cd 100644
--- a/internal_packages/preferences/lib/tabs/preferences-general.cjsx
+++ b/internal_packages/preferences/lib/tabs/preferences-general.cjsx
@@ -1,7 +1,7 @@
 React = require 'react'
 _ = require 'underscore'
 {RetinaImg, Flexbox} = require 'nylas-component-kit'
-{LaunchServices} = require 'nylas-exports'
+{LaunchServices, AccountStore} = require 'nylas-exports'
 
 class PreferencesGeneral extends React.Component
   @displayName: 'PreferencesGeneral'
@@ -22,15 +22,30 @@ class PreferencesGeneral extends React.Component
       @setState(defaultClient: true)
       @_services.registerForURLScheme('mailto')
 
+  toggleShowImportant: (event) =>
+    @props.config.toggle('core.showImportant')
+    event.preventDefault()
+
+  _renderImportanceOptionElement: =>
+    return false unless AccountStore.current().usesImportantFlag()
+    importanceOptionElement = <div className="section-header">
+      <input type="checkbox" id="show-important"
+             checked={@props.config.get('core.showImportant')}
+             onChange={@toggleShowImportant}/>
+      <label htmlFor="show-important">Show Gmail-style important markers</label>
+    </div>
+
   render: =>
     <div className="container-notifications">
       <div className="section">
-        <div className="section-header platform-darwin-only" style={marginBottom:30}>
+        <div className="section-header platform-darwin-only">
           <input type="checkbox" id="default-client" checked={@state.defaultClient} onChange={@toggleDefaultMailClient}/>
           <label htmlFor="default-client">Use Nylas as my default mail client</label>
         </div>
 
-        <div className="section-header">
+        {@_renderImportanceOptionElement()}
+
+        <div className="section-header" style={marginTop:30}>
           Delay for marking messages as read:
           <select value={@props.config.get('core.reading.markAsReadDelay')}
                   onChange={ (event) => @props.config.set('core.reading.markAsReadDelay', event.target.value) }>
diff --git a/internal_packages/thread-list/lib/thread-list-icon.cjsx b/internal_packages/thread-list/lib/thread-list-icon.cjsx
index 80ebef54d..0b02fe86a 100644
--- a/internal_packages/thread-list/lib/thread-list-icon.cjsx
+++ b/internal_packages/thread-list/lib/thread-list-icon.cjsx
@@ -30,7 +30,7 @@ class ThreadListIcon extends React.Component
       else
         return 'thread-icon-replied thread-icon-star-on-hover'
 
-    return 'thread-icon-star-on-hover'
+    return 'thread-icon-none thread-icon-star-on-hover'
 
   _nonDraftMessages: =>
     msgs = @props.thread.metadata
diff --git a/internal_packages/thread-list/lib/thread-list.cjsx b/internal_packages/thread-list/lib/thread-list.cjsx
index ef18deef0..a642a0730 100644
--- a/internal_packages/thread-list/lib/thread-list.cjsx
+++ b/internal_packages/thread-list/lib/thread-list.cjsx
@@ -18,6 +18,7 @@ ThreadListStore = require './thread-list-store'
 ThreadListIcon = require './thread-list-icon'
 
 EmptyState = require './empty-state'
+{MailImportantIcon} = require 'nylas-component-kit'
 
 class ThreadListScrollTooltip extends React.Component
   @displayName: 'ThreadListScrollTooltip'
@@ -65,7 +66,10 @@ class ThreadList extends React.Component
     c1 = new ListTabular.Column
       name: "★"
       resolver: (thread) =>
-        <ThreadListIcon thread={thread} />
+        <span>
+          <ThreadListIcon thread={thread} />
+          <MailImportantIcon thread={thread} />
+        </span>
 
     c2 = new ListTabular.Column
       name: "Participants"
@@ -96,12 +100,13 @@ class ThreadList extends React.Component
 
         currentCategoryId = FocusedMailViewStore.mailView()?.categoryId()
         allCategoryId = CategoryStore.getStandardCategory('all')?.id
-        ignoredIds = [currentCategoryId, allCategoryId]
+
+        ignoredIds = [currentCategoryId]
+        ignoredIds.push(cat.id) for cat in CategoryStore.getHiddenCategories()
 
         for label in (thread.sortedLabels())
           continue if label.id in ignoredIds
-          if not c3LabelComponentCache[label.id]
-            c3LabelComponentCache[label.id] = <MailLabel label={label} key={label.id} />
+          c3LabelComponentCache[label.id] ?= <MailLabel label={label} key={label.id} />
           labels.push c3LabelComponentCache[label.id]
 
         <span className="details">
@@ -147,6 +152,7 @@ class ThreadList extends React.Component
             {attachment}
             <span className="timestamp">{timestamp(thread.lastMessageReceivedTimestamp)}</span>
           </div>
+          <MailImportantIcon thread={thread} />
           <div className="subject">{subject(thread.subject)}</div>
           <div className="snippet">{thread.snippet}</div>
         </div>
diff --git a/internal_packages/thread-list/stylesheets/thread-list.less b/internal_packages/thread-list/stylesheets/thread-list.less
index 7d1fab204..9aff6b80a 100644
--- a/internal_packages/thread-list/stylesheets/thread-list.less
+++ b/internal_packages/thread-list/stylesheets/thread-list.less
@@ -22,7 +22,7 @@
     color: @text-color-inverse-subtle;
   }
 
-  .thread-icon, .draft-icon {
+  .thread-icon, .draft-icon, .mail-important-icon {
     -webkit-filter: brightness(600%) grayscale(100%);
   }
 
@@ -58,6 +58,16 @@
     border-bottom: 1px solid fade(@list-border, 60%);
   }
 
+  .mail-important-icon {
+    margin-top:1px;
+    margin-left:6px;
+    padding: 12px;
+    vertical-align: initial;
+    &:not(.active) {
+      visibility: hidden;
+    }
+  }
+
   .message-count {
     color: @text-color-inverse;
     background: @background-tertiary;
@@ -157,6 +167,7 @@
     width:15px;
     height:15px;
     background-size: 15px;
+    display:inline-block;
     background-repeat: no-repeat;
     background-position:center;
     padding:12px;
@@ -261,10 +272,18 @@
 
 // stars
 
-.thread-list .thread-icon-star:hover {
+.thread-list .thread-icon-star:hover,
+.thread-list .list-item:hover .thread-icon-none:hover {
   background-image:url(../static/images/thread-list/icon-star-action-hover-@2x.png);
   background-size: 16px;
 }
+.thread-list .list-item:hover .thread-icon-none {
+  background-image:url(../static/images/thread-list/icon-star-hover-@2x.png);
+  background-size: 16px;
+}
+.thread-list .list-item:hover .mail-important-icon {
+  visibility: inherit;
+}
 .thread-list .thread-icon-star-on-hover:hover {
   background-image:url(../static/images/thread-list/icon-star-hover-@2x.png);
   background-size: 16px;
@@ -280,6 +299,15 @@
   .thread-icon {
     margin-right:6px;
   }
+
+  .mail-important-icon {
+    margin-top:1px;
+    margin-left:1px;
+    float:left;
+    padding: 12px;
+    vertical-align: initial;
+  }
+
   .subject {
     font-size: @font-size-base;
     overflow: hidden;
diff --git a/src/components/mail-important-icon.cjsx b/src/components/mail-important-icon.cjsx
new file mode 100644
index 000000000..14116a3d5
--- /dev/null
+++ b/src/components/mail-important-icon.cjsx
@@ -0,0 +1,55 @@
+_ = require 'underscore'
+React = require 'react'
+{Actions,
+ Utils,
+ Thread,
+ ChangeLabelsTask,
+ CategoryStore,
+ AccountStore} = require 'nylas-exports'
+
+class MailImportantIcon extends React.Component
+  @displayName: 'MailImportantIcon'
+  @propTypes:
+    thread: React.PropTypes.object
+
+  constructor: (@props) ->
+    @state = @getStateFromStores()
+
+  getStateFromStores: =>
+    showing: AccountStore.current().usesImportantFlag() and atom.config.get('core.showImportant')
+
+  componentDidMount: =>
+    @subscription = atom.config.observe 'core.showImportant', =>
+      @setState(@getStateFromStores())
+
+  componentWillUnmount: =>
+    @subscription?.dispose()
+
+  shouldComponentUpdate: (nextProps, nextState) =>
+    return false if nextProps.thread is @props.thread and @state.showing is nextState.showing
+    true
+
+  render: =>
+    return false unless @state.showing
+
+    importantId = CategoryStore.getStandardCategory('important').id
+    isImportant = _.findWhere(@props.thread.labels, {id: importantId})?
+
+    activeClassname = if isImportant then "active" else ""
+    <div className="mail-important-icon #{activeClassname}" onClick={@_onToggleImportant}></div>
+
+  _onToggleImportant: (event) =>
+    importantLabel = CategoryStore.getStandardCategory('important')
+    isImportant = _.findWhere(@props.thread.labels, {id: importantLabel.id})?
+
+    if isImportant
+      task = new ChangeLabelsTask(thread: @props.thread, labelsToRemove: [importantLabel], labelsToAdd: [])
+    else
+      task = new ChangeLabelsTask(thread: @props.thread, labelsToAdd: [importantLabel], labelsToRemove: [])
+
+    Actions.queueTask(task)
+
+    # Don't trigger the thread row click
+    event.stopPropagation()
+
+module.exports = MailImportantIcon
diff --git a/src/config-schema.coffee b/src/config-schema.coffee
index 9db26d4b6..54a3f11ad 100644
--- a/src/config-schema.coffee
+++ b/src/config-schema.coffee
@@ -10,6 +10,9 @@ module.exports =
       showUnreadBadge:
         type: 'boolean'
         default: true
+      showImportant:
+        type: 'boolean'
+        default: true
       disabledPackages:
         type: 'array'
         default: []
diff --git a/src/flux/models/account.coffee b/src/flux/models/account.coffee
index bf64d81f7..38fac5651 100644
--- a/src/flux/models/account.coffee
+++ b/src/flux/models/account.coffee
@@ -66,4 +66,7 @@ class Account extends Model
       return 'Gmail'
     return @provider
 
+  usesImportantFlag: ->
+    @provider is 'gmail'
+
 module.exports = Account
diff --git a/src/flux/stores/category-store.coffee b/src/flux/stores/category-store.coffee
index d340ee4fe..a719a8a7a 100644
--- a/src/flux/stores/category-store.coffee
+++ b/src/flux/stores/category-store.coffee
@@ -9,8 +9,14 @@ AccountStore = require './account-store'
 class CategoryStore extends NylasStore
   constructor: ->
     @_categoryCache = {}
+    @_standardCategories = []
+    @_userCategories = []
+    @_hiddenCategories = []
+
     @listenTo DatabaseStore, @_onDBChanged
     @listenTo AccountStore, @_refreshCacheFromDB
+    atom.config.observe 'core.showImportant', => @_refreshCacheFromDB()
+
     @_refreshCacheFromDB()
 
   # We look for a few standard categories and display them in the Mailboxes
@@ -37,6 +43,7 @@ class CategoryStore extends NylasStore
     "all"
     "archive"
     "starred"
+    "important"
   ]
 
   AllMailName: "all"
@@ -69,7 +76,6 @@ class CategoryStore extends NylasStore
   #
   getCategories: -> _.values @_categoryCache
 
-
   # Public: Returns the Folder or Label object for a standard category name.
   # ('inbox', 'drafts', etc.) It's possible for this to return `null`.
   # For example, Gmail likely doesn't have an `archive` label.
@@ -82,25 +88,20 @@ class CategoryStore extends NylasStore
   # Public: Returns all of the standard categories for the current account.
   #
   getStandardCategories: ->
-    # Single pass to create lookup table, single pass to get ordered array
-    byStandardName = {}
-    for key, val of @_categoryCache
-      byStandardName[val.name] = val
-    _.compact @StandardCategoryNames.map (name) =>
-      byStandardName[name]
+    @_standardCategories
 
   getUnhiddenStandardCategories: ->
     @getStandardCategories().filter (c) ->
       not _.contains @HiddenCategoryNames, c.name
 
+  getHiddenCategories: ->
+    @_hiddenCategories
+
   # Public: Returns all of the categories that are not part of the standard
   # category set.
   #
   getUserCategories: ->
-    userCategories = _.reject _.values(@_categoryCache), (cat) =>
-      cat.name in @StandardCategoryNames or cat.name in @HiddenCategoryNames
-    userCategories = _.sortBy(userCategories, 'displayName')
-    return _.compact(userCategories)
+    @_userCategories
 
   _onDBChanged: (change) ->
     categoryClass = @categoryClass()
@@ -117,6 +118,29 @@ class CategoryStore extends NylasStore
     DatabaseStore.findAll(categoryClass).where(categoryClass.attributes.accountId.equal(account.id)).then (categories=[]) =>
       @_categoryCache = {}
       @_categoryCache[category.id] = category for category in categories
+
+      # Compute user categories
+      userCategories = _.reject _.values(@_categoryCache), (cat) =>
+        cat.name in @StandardCategoryNames or cat.name in @HiddenCategoryNames
+      userCategories = _.sortBy(userCategories, 'displayName')
+      @_userCategories =  _.compact(userCategories)
+
+      # Compute hidden categories
+      @_hiddenCategories = _.filter _.values(@_categoryCache), (cat) =>
+        cat.name in @HiddenCategoryNames
+
+      # Compute standard categories
+      # Single pass to create lookup table, single pass to get ordered array
+      byStandardName = {}
+      for key, val of @_categoryCache
+        byStandardName[val.name] = val
+
+      if not atom.config.get('core.showImportant')
+        delete byStandardName['important']
+
+      @_standardCategories = _.compact @StandardCategoryNames.map (name) =>
+        byStandardName[name]
+
       @trigger()
 
 module.exports = new CategoryStore()
diff --git a/static/components/extra.less b/static/components/extra.less
index 5d246d92a..bccb78c54 100644
--- a/static/components/extra.less
+++ b/static/components/extra.less
@@ -61,3 +61,23 @@
     opacity: 1;
   }
 }
+
+
+.mail-important-icon {
+  width:16px;
+  height:16px;
+  vertical-align: middle;
+  display:inline-block;
+  background-repeat: no-repeat;
+  background-position:center;
+  background-image:url(../static/images/important/Icon-Important-Hover@2x.png);
+  background-size: 16px;
+}
+.mail-important-icon.active {
+  background-image:url(../static/images/important/Icon-Important-Active@2x.png);
+  background-size: 16px;
+}
+.mail-important-icon:hover {
+  background-image:url(../static/images/important/Icon-Important-HoverActive@2x.png);
+  background-size: 16px;
+}
diff --git a/static/images/important/Icon-Important-Active@2x.png b/static/images/important/Icon-Important-Active@2x.png
new file mode 100644
index 000000000..fd85eddcc
Binary files /dev/null and b/static/images/important/Icon-Important-Active@2x.png differ
diff --git a/static/images/important/Icon-Important-Hover@2x.png b/static/images/important/Icon-Important-Hover@2x.png
new file mode 100644
index 000000000..b9a3b4414
Binary files /dev/null and b/static/images/important/Icon-Important-Hover@2x.png differ
diff --git a/static/images/important/Icon-Important-HoverActive@2x.png b/static/images/important/Icon-Important-HoverActive@2x.png
new file mode 100644
index 000000000..22b696334
Binary files /dev/null and b/static/images/important/Icon-Important-HoverActive@2x.png differ