diff --git a/features/config_tracked_files.feature b/features/config_tracked_files.feature
new file mode 100644
index 00000000..ba0c4f0c
--- /dev/null
+++ b/features/config_tracked_files.feature
@@ -0,0 +1,29 @@
+@test_unit
+Feature:
+
+  Using the setting `tracked_files` should add files that were not
+  required to the report.
+
+  Scenario:
+    Given SimpleCov for Test/Unit is configured with:
+      """
+      require 'simplecov'
+      SimpleCov.start do
+        track_files "lib/**/*.rb"
+      end
+      """
+
+    When I open the coverage report generated with `bundle exec rake test`
+    Then I should see the groups:
+      | name      | coverage | files |
+      | All Files | 76.81%   | 7     |
+
+    And I should see the source files:
+      | name                                    | coverage |
+      | lib/faked_project.rb                    | 100.0 %  |
+      | lib/faked_project/untested_class.rb     | 0.0 %    |
+      | lib/faked_project/some_class.rb         | 80.0 %   |
+      | lib/faked_project/framework_specific.rb | 75.0 %   |
+      | lib/faked_project/meta_magic.rb         | 100.0 %  |
+      | test/meta_magic_test.rb                 | 100.0 %  |
+      | test/some_class_test.rb                 | 100.0 %  |
diff --git a/lib/simplecov.rb b/lib/simplecov.rb
index f4a555ea..95da3ebd 100644
--- a/lib/simplecov.rb
+++ b/lib/simplecov.rb
@@ -48,12 +48,29 @@ def start(profile = nil, &block)
       end
     end
 
+    #
+    # Finds files that were to be tracked but were not loaded and initializes
+    # their coverage to zero.
+    #
+    def add_not_loaded_files(result)
+      if @track_files_glob
+        result = result.dup
+        Dir[@track_files_glob].each do |file|
+          absolute = File.expand_path(file)
+
+          result[absolute] ||= [0] * File.foreach(absolute).count
+        end
+      end
+
+      result
+    end
+
     #
     # Returns the result for the current coverage run, merging it across test suites
     # from cache using SimpleCov::ResultMerger if use_merging is activated (default)
     #
     def result
-      @result ||= SimpleCov::Result.new(Coverage.result) if running
+      @result ||= SimpleCov::Result.new(add_not_loaded_files(Coverage.result)) if running
       # If we're using merging of results, store the current result
       # first, then merge the results and return those
       if use_merging
diff --git a/lib/simplecov/configuration.rb b/lib/simplecov/configuration.rb
index 3e0d6c46..d7d20da5 100644
--- a/lib/simplecov/configuration.rb
+++ b/lib/simplecov/configuration.rb
@@ -42,6 +42,15 @@ def coverage_path
       coverage_path
     end
 
+    #
+    # Coverage results will always include files matched by this glob, whether
+    # or not they were explicitly required. Without this, un-required files
+    # will not be present in the final report.
+    #
+    def track_files(glob)
+      @track_files_glob = glob
+    end
+
     #
     # Returns the list of configured filters. Add filters using SimpleCov.add_filter.
     #
diff --git a/lib/simplecov/defaults.rb b/lib/simplecov/defaults.rb
index 09aad1c1..c60d9d6b 100644
--- a/lib/simplecov/defaults.rb
+++ b/lib/simplecov/defaults.rb
@@ -32,6 +32,8 @@
   add_group "Mailers", "app/mailers"
   add_group "Helpers", "app/helpers"
   add_group "Libraries", "lib"
+
+  track_files "{app,lib}/**/*.rb"
 end
 
 # Default configuration
diff --git a/spec/faked_project/lib/faked_project.rb b/spec/faked_project/lib/faked_project.rb
index c33c7917..ba5c49d7 100644
--- a/spec/faked_project/lib/faked_project.rb
+++ b/spec/faked_project/lib/faked_project.rb
@@ -4,7 +4,7 @@ def self.foo
   end
 end
 
-Dir[File.join(File.dirname(__FILE__), "faked_project/*.rb")].each do |file|
+Dir[File.join(File.dirname(__FILE__), "faked_project/*.rb")].reject { |f| /untested/.match(f) }.each do |file|
   require file # Require all source files in project dynamically so we can inject some stuff depending on test situation
 end
 
diff --git a/spec/faked_project/lib/faked_project/untested_class.rb b/spec/faked_project/lib/faked_project/untested_class.rb
new file mode 100644
index 00000000..dc03d0f9
--- /dev/null
+++ b/spec/faked_project/lib/faked_project/untested_class.rb
@@ -0,0 +1,11 @@
+class UntestedClass
+  def initialize(yogurts)
+    @yogurts = yogurts
+  end
+
+  def power_level
+    @yogurts.map do |yo|
+      yo.experience_points**2
+    end.reduce(0, &:+)
+  end
+end