diff --git a/src/app/atom.coffee b/src/app/atom.coffee
index 945ba0085..14c741cab 100644
--- a/src/app/atom.coffee
+++ b/src/app/atom.coffee
@@ -50,7 +50,7 @@ _.extend atom,
       .filter (name) -> not _.contains(disabledPackages, name)
 
   loadThemes: ->
-    themeNames = config.get("core.themes") ? ['atom-dark', 'github-dark']
+    themeNames = config.get("core.themes") ? ['atom-ui-dark', 'atom-syntax-dark']
     themeNames = [themeNames] unless _.isArray(themeNames)
     @loadTheme(themeName) for themeName in themeNames
     @loadUserStylesheet()
@@ -64,7 +64,7 @@ _.extend atom,
       applyStylesheet(userStylesheetPath, fs.read(userStylesheetPath), 'userTheme')
 
   getAtomThemeStylesheets: ->
-    themeNames = config.get("core.themes") ? ['Atom - Dark', 'GitHub_Dark']
+    themeNames = config.get("core.themes") ? ['atom-ui-dark', 'atom-syntax-dark']
     themeNames = [themeNames] unless _.isArray(themeNames)
 
   open: (args...) ->
diff --git a/themes/github-dark.css b/themes/atom-syntax-dark.css
similarity index 100%
rename from themes/github-dark.css
rename to themes/atom-syntax-dark.css
diff --git a/themes/github-light.css b/themes/atom-syntax-light.css
similarity index 100%
rename from themes/github-light.css
rename to themes/atom-syntax-light.css
diff --git a/themes/atom-dark/atom.css b/themes/atom-ui-dark/atom.css
similarity index 100%
rename from themes/atom-dark/atom.css
rename to themes/atom-ui-dark/atom.css
diff --git a/themes/atom-dark/autocomplete.css b/themes/atom-ui-dark/autocomplete.css
similarity index 100%
rename from themes/atom-dark/autocomplete.css
rename to themes/atom-ui-dark/autocomplete.css
diff --git a/themes/atom-dark/command-logger.css b/themes/atom-ui-dark/command-logger.css
similarity index 100%
rename from themes/atom-dark/command-logger.css
rename to themes/atom-ui-dark/command-logger.css
diff --git a/themes/atom-dark/command-palette.css b/themes/atom-ui-dark/command-palette.css
similarity index 100%
rename from themes/atom-dark/command-palette.css
rename to themes/atom-ui-dark/command-palette.css
diff --git a/themes/atom-dark/command-panel.css b/themes/atom-ui-dark/command-panel.css
similarity index 100%
rename from themes/atom-dark/command-panel.css
rename to themes/atom-ui-dark/command-panel.css
diff --git a/themes/atom-dark/editor.css b/themes/atom-ui-dark/editor.css
similarity index 100%
rename from themes/atom-dark/editor.css
rename to themes/atom-ui-dark/editor.css
diff --git a/themes/atom-dark/fuzzy-finder.css b/themes/atom-ui-dark/fuzzy-finder.css
similarity index 100%
rename from themes/atom-dark/fuzzy-finder.css
rename to themes/atom-ui-dark/fuzzy-finder.css
diff --git a/themes/atom-dark/gists.css b/themes/atom-ui-dark/gists.css
similarity index 100%
rename from themes/atom-dark/gists.css
rename to themes/atom-ui-dark/gists.css
diff --git a/themes/atom-dark/go-to-line.css b/themes/atom-ui-dark/go-to-line.css
similarity index 100%
rename from themes/atom-dark/go-to-line.css
rename to themes/atom-ui-dark/go-to-line.css
diff --git a/themes/atom-dark/grammar-view.css b/themes/atom-ui-dark/grammar-view.css
similarity index 100%
rename from themes/atom-dark/grammar-view.css
rename to themes/atom-ui-dark/grammar-view.css
diff --git a/themes/atom-dark/markdown-preview.css b/themes/atom-ui-dark/markdown-preview.css
similarity index 100%
rename from themes/atom-dark/markdown-preview.css
rename to themes/atom-ui-dark/markdown-preview.css
diff --git a/themes/atom-dark/package.json b/themes/atom-ui-dark/package.json
similarity index 100%
rename from themes/atom-dark/package.json
rename to themes/atom-ui-dark/package.json
diff --git a/themes/atom-dark/select-list.css b/themes/atom-ui-dark/select-list.css
similarity index 100%
rename from themes/atom-dark/select-list.css
rename to themes/atom-ui-dark/select-list.css
diff --git a/themes/atom-dark/status-bar.css b/themes/atom-ui-dark/status-bar.css
similarity index 100%
rename from themes/atom-dark/status-bar.css
rename to themes/atom-ui-dark/status-bar.css
diff --git a/themes/atom-dark/symbols-view.css b/themes/atom-ui-dark/symbols-view.css
similarity index 100%
rename from themes/atom-dark/symbols-view.css
rename to themes/atom-ui-dark/symbols-view.css
diff --git a/themes/atom-dark/tabs.css b/themes/atom-ui-dark/tabs.css
similarity index 100%
rename from themes/atom-dark/tabs.css
rename to themes/atom-ui-dark/tabs.css
diff --git a/themes/atom-dark/tree-view.css b/themes/atom-ui-dark/tree-view.css
similarity index 100%
rename from themes/atom-dark/tree-view.css
rename to themes/atom-ui-dark/tree-view.css
diff --git a/themes/atom-dark/wrap-guide.css b/themes/atom-ui-dark/wrap-guide.css
similarity index 100%
rename from themes/atom-dark/wrap-guide.css
rename to themes/atom-ui-dark/wrap-guide.css
diff --git a/themes/atom-light/atom.css b/themes/atom-ui-light/atom.css
similarity index 100%
rename from themes/atom-light/atom.css
rename to themes/atom-ui-light/atom.css
diff --git a/themes/atom-light/autocomplete.css b/themes/atom-ui-light/autocomplete.css
similarity index 100%
rename from themes/atom-light/autocomplete.css
rename to themes/atom-ui-light/autocomplete.css
diff --git a/themes/atom-light/command-logger.css b/themes/atom-ui-light/command-logger.css
similarity index 100%
rename from themes/atom-light/command-logger.css
rename to themes/atom-ui-light/command-logger.css
diff --git a/themes/atom-light/command-palette.css b/themes/atom-ui-light/command-palette.css
similarity index 100%
rename from themes/atom-light/command-palette.css
rename to themes/atom-ui-light/command-palette.css
diff --git a/themes/atom-light/command-panel.css b/themes/atom-ui-light/command-panel.css
similarity index 100%
rename from themes/atom-light/command-panel.css
rename to themes/atom-ui-light/command-panel.css
diff --git a/themes/atom-light/editor.css b/themes/atom-ui-light/editor.css
similarity index 100%
rename from themes/atom-light/editor.css
rename to themes/atom-ui-light/editor.css
diff --git a/themes/atom-light/fuzzy-finder.css b/themes/atom-ui-light/fuzzy-finder.css
similarity index 100%
rename from themes/atom-light/fuzzy-finder.css
rename to themes/atom-ui-light/fuzzy-finder.css
diff --git a/themes/atom-light/gists.css b/themes/atom-ui-light/gists.css
similarity index 100%
rename from themes/atom-light/gists.css
rename to themes/atom-ui-light/gists.css
diff --git a/themes/atom-light/go-to-line.css b/themes/atom-ui-light/go-to-line.css
similarity index 100%
rename from themes/atom-light/go-to-line.css
rename to themes/atom-ui-light/go-to-line.css
diff --git a/themes/atom-light/grammar-view.css b/themes/atom-ui-light/grammar-view.css
similarity index 100%
rename from themes/atom-light/grammar-view.css
rename to themes/atom-ui-light/grammar-view.css
diff --git a/themes/atom-light/markdown-preview.css b/themes/atom-ui-light/markdown-preview.css
similarity index 100%
rename from themes/atom-light/markdown-preview.css
rename to themes/atom-ui-light/markdown-preview.css
diff --git a/themes/atom-light/package.json b/themes/atom-ui-light/package.json
similarity index 100%
rename from themes/atom-light/package.json
rename to themes/atom-ui-light/package.json
diff --git a/themes/atom-light/select-list.css b/themes/atom-ui-light/select-list.css
similarity index 100%
rename from themes/atom-light/select-list.css
rename to themes/atom-ui-light/select-list.css
diff --git a/themes/atom-light/status-bar.css b/themes/atom-ui-light/status-bar.css
similarity index 100%
rename from themes/atom-light/status-bar.css
rename to themes/atom-ui-light/status-bar.css
diff --git a/themes/atom-light/symbols-view.css b/themes/atom-ui-light/symbols-view.css
similarity index 100%
rename from themes/atom-light/symbols-view.css
rename to themes/atom-ui-light/symbols-view.css
diff --git a/themes/atom-light/tabs.css b/themes/atom-ui-light/tabs.css
similarity index 100%
rename from themes/atom-light/tabs.css
rename to themes/atom-ui-light/tabs.css
diff --git a/themes/atom-light/tree-view.css b/themes/atom-ui-light/tree-view.css
similarity index 100%
rename from themes/atom-light/tree-view.css
rename to themes/atom-ui-light/tree-view.css
diff --git a/themes/atom-light/wrap-guide.css b/themes/atom-ui-light/wrap-guide.css
similarity index 100%
rename from themes/atom-light/wrap-guide.css
rename to themes/atom-ui-light/wrap-guide.css