diff --git a/.gitignore b/.gitignore
index c055484..4f1e3e7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,2 @@
 bin
-test/tmp
+test/tmp
\ No newline at end of file
diff --git a/Gemfile.lock b/Gemfile.lock
index b3f2dd4..ffe788a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,51 +1,36 @@
 PATH
   remote: .
   specs:
-    cache_digests (0.3.0)
+    cache_digests (0.3.1)
       actionpack (>= 3.2)
       thread_safe
 
 GEM
   remote: https://rubygems.org/
   specs:
-    actionpack (3.2.13)
-      activemodel (= 3.2.13)
-      activesupport (= 3.2.13)
-      builder (~> 3.0.0)
+    actionpack (4.0.12)
+      activesupport (= 4.0.12)
+      builder (~> 3.1.0)
       erubis (~> 2.7.0)
-      journey (~> 1.0.4)
-      rack (~> 1.4.5)
-      rack-cache (~> 1.2)
-      rack-test (~> 0.6.1)
-      sprockets (~> 2.2.1)
-    activemodel (3.2.13)
-      activesupport (= 3.2.13)
-      builder (~> 3.0.0)
-    activesupport (3.2.13)
-      i18n (= 0.6.1)
-      multi_json (~> 1.0)
-    atomic (1.1.8)
-    builder (3.0.4)
+      rack (~> 1.5.2)
+      rack-test (~> 0.6.2)
+    activesupport (4.0.12)
+      i18n (~> 0.6, >= 0.6.9)
+      minitest (~> 4.2)
+      multi_json (~> 1.3)
+      thread_safe (~> 0.1)
+      tzinfo (~> 0.3.37)
+    builder (3.1.4)
     erubis (2.7.0)
-    hike (1.2.2)
-    i18n (0.6.1)
-    journey (1.0.4)
+    i18n (0.7.0)
     minitest (4.7.3)
-    multi_json (1.7.2)
-    rack (1.4.5)
-    rack-cache (1.2)
-      rack (>= 0.4)
+    multi_json (1.10.1)
+    rack (1.5.2)
     rack-test (0.6.2)
       rack (>= 1.0)
     rake (10.0.4)
-    sprockets (2.2.2)
-      hike (~> 1.2)
-      multi_json (~> 1.0)
-      rack (~> 1.0)
-      tilt (~> 1.1, != 1.3.0)
-    thread_safe (0.1.0)
-      atomic
-    tilt (1.3.7)
+    thread_safe (0.3.4)
+    tzinfo (0.3.42)
 
 PLATFORMS
   ruby
diff --git a/lib/cache_digests/dependency_tracker.rb b/lib/cache_digests/dependency_tracker.rb
index d258ddc..c938558 100644
--- a/lib/cache_digests/dependency_tracker.rb
+++ b/lib/cache_digests/dependency_tracker.rb
@@ -38,7 +38,7 @@ class ERBTracker
       RENDER_DEPENDENCY = /
         render\s*                     # render, followed by optional whitespace
         \(?                           # start an optional parenthesis for the render call
-        (partial:|:partial\s+=>)?\s*  # naming the partial, used with collection -- 1st capture
+        (partial:|:partial\s+=>|layout:|:layout\s+=>)?\s*  # naming the partial, used with collection -- 1st capture
         ([@a-z"'][@\w\/\."']+)        # the template name itself -- 2nd capture
       /x
 
diff --git a/test/fixtures/layouts/_shared.html.erb b/test/fixtures/layouts/_shared.html.erb
new file mode 100644
index 0000000..0b4a917
--- /dev/null
+++ b/test/fixtures/layouts/_shared.html.erb
@@ -0,0 +1,3 @@
+<div class="layout-container">
+  <%=yield %>
+</div>
\ No newline at end of file
diff --git a/test/fixtures/layouts/index.html.erb b/test/fixtures/layouts/index.html.erb
new file mode 100644
index 0000000..3177015
--- /dev/null
+++ b/test/fixtures/layouts/index.html.erb
@@ -0,0 +1,3 @@
+<%= render layout: "layouts/shared" do %>
+  Hello world
+<% end %>
diff --git a/test/template_digestor_test.rb b/test/template_digestor_test.rb
index d20c6ab..1a2ffa3 100644
--- a/test/template_digestor_test.rb
+++ b/test/template_digestor_test.rb
@@ -8,7 +8,7 @@ class MissingTemplate < StandardError
 
 class FixtureTemplate
   attr_reader :source, :handler
-  
+
   def initialize(template_path, handler = :erb)
     @source = File.read(template_path)
     @handler = handler
@@ -20,7 +20,7 @@ def initialize(template_path, handler = :erb)
 class FixtureFinder
   FIXTURES_DIR = "#{File.dirname(__FILE__)}/fixtures"
   TMP_DIR      = "#{File.dirname(__FILE__)}/tmp"
-  
+
   def find(logical_name, keys, partial, options)
     FixtureTemplate.new("#{TMP_DIR}/#{partial ? logical_name.gsub(%r|/([^/]+)$|, '/_\1') : logical_name}.#{options[:formats].first}.erb")
   end
@@ -31,7 +31,7 @@ def setup
     FileUtils.cp_r FixtureFinder::FIXTURES_DIR, FixtureFinder::TMP_DIR
     CacheDigests::DependencyTracker.register_tracker :erb, CacheDigests::DependencyTracker::ERBTracker
   end
-  
+
   def teardown
     FileUtils.rm_r FixtureFinder::TMP_DIR
     CacheDigests::TemplateDigestor.cache.clear
@@ -88,7 +88,13 @@ def test_third_level_dependency
       change_template("comments/_comment")
     end
   end
-  
+
+  def test_layout_dependency
+    assert_digest_difference("layouts/index") do
+      change_template("layouts/_shared")
+    end
+  end
+
   def test_directory_depth_dependency
     assert_digest_difference("level/below/index") do
       change_template("level/below/_header")
@@ -112,11 +118,11 @@ def test_nested_template_directory
       change_template("messages/actions/_move")
     end
   end
-  
+
   def test_recursion_in_renders
     assert digest("level/recursion")
   end
-  
+
   def test_dont_generate_a_digest_for_missing_templates
     assert_equal '', digest("nothing/there")
   end
@@ -130,13 +136,18 @@ def test_collection_dependency
       change_template("events/_event")
     end
   end
-  
+
   def test_collection_derived_from_record_dependency
     assert_digest_difference("messages/show") do
       change_template("events/_event")
     end
   end
 
+  def test_layout_source_changed
+    assert_digest_difference("layouts/index") do
+      change_string_in_template("layouts/index", "<% end %>", "hi!\n<% end %>")
+    end
+  end
 
   private
     def assert_logged(message)
@@ -144,10 +155,10 @@ def assert_logged(message)
       CacheDigests::TemplateDigestor.logger = Logger.new(log)
 
       yield
-      
+
       log.rewind
       assert_match message, log.read
-      
+
       CacheDigests::TemplateDigestor.logger = nil
     end
 
@@ -160,14 +171,21 @@ def assert_digest_difference(template_name)
       assert previous_digest != digest(template_name), "digest didn't change"
       CacheDigests::TemplateDigestor.cache.clear
     end
-  
+
     def digest(template_name, options={})
       CacheDigests::TemplateDigestor.digest(template_name, :html, FixtureFinder.new, options)
     end
-    
-    def change_template(template_name)
-      File.open("#{FixtureFinder::TMP_DIR}/#{template_name}.html.erb", "w") do |f|
+
+    def change_template(template_name, ext = 'erb')
+      File.open("#{FixtureFinder::TMP_DIR}/#{template_name}.html.#{ext}", "w") do |f|
         f.write "\nTHIS WAS CHANGED!"
       end
     end
+
+    def change_string_in_template(template_name, original_string, replace_with, ext = 'erb')
+      file_name = "#{FixtureFinder::TMP_DIR}/#{template_name}.html.#{ext}"
+      text = File.read(file_name)
+      new_contents = text.gsub(original_string, replace_with)
+      File.open(file_name, "w") {|file| file.puts new_contents }
+    end
 end