diff --git a/lib/google/api_client/client_secrets.rb b/lib/google/api_client/client_secrets.rb
new file mode 100644
index 000000000..ab299d614
--- /dev/null
+++ b/lib/google/api_client/client_secrets.rb
@@ -0,0 +1,105 @@
+# Copyright 2010 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+require 'multi_json'
+
+
+module Google
+  class APIClient
+    ##
+    # Manages the persistence of client configuration data and secrets.
+    class ClientSecrets
+      def self.load(filename=nil)
+        if filename && File.directory?(filename)
+          search_path = File.expand_path(filename)
+          filename = nil
+        end
+        while filename == nil
+          search_path ||= File.expand_path('.')
+          puts search_path
+          if File.exist?(File.join(search_path, 'client_secrets.json'))
+            filename = File.join(search_path, 'client_secrets.json')
+          elsif search_path == '/' || search_path =~ /[a-zA-Z]:[\/\\]/
+            raise ArgumentError,
+              'No client_secrets.json filename supplied ' +
+              'and/or could not be found in search path.'
+          else
+            search_path = File.expand_path(File.join(search_path, '..'))
+          end
+        end
+        data = File.open(filename, 'r') { |file| MultiJson.decode(file.read) }
+        return self.new(data)
+      end
+
+      def initialize(options={})
+        # Client auth configuration
+        @flow = options[:flow] || options.keys.first.to_s || 'web'
+        fdata = options[@flow]
+        @client_id = fdata[:client_id] || fdata["client_id"]
+        @client_secret = fdata[:client_secret] || fdata["client_secret"]
+        @redirect_uris = fdata[:redirect_uris] || fdata["redirect_uris"]
+        @redirect_uris ||= [fdata[:redirect_uri]]
+        @javascript_origins = (
+          fdata[:javascript_origins] ||
+          fdata["javascript_origins"]
+        )
+        @javascript_origins ||= [fdata[:javascript_origin]]
+        @authorization_uri = fdata[:auth_uri] || fdata["auth_uri"]
+        @authorization_uri ||= fdata[:authorization_uri]
+        @token_credential_uri = fdata[:token_uri] || fdata["token_uri"]
+        @token_credential_uri ||= fdata[:token_credential_uri]
+
+        # Associated token info
+        @access_token = fdata[:access_token] || fdata["access_token"]
+        @refresh_token = fdata[:refresh_token] || fdata["refresh_token"]
+        @id_token = fdata[:id_token] || fdata["id_token"]
+        @expires_in = fdata[:expires_in] || fdata["expires_in"]
+        @expires_at = fdata[:expires_at] || fdata["expires_at"]
+        @issued_at = fdata[:issued_at] || fdata["issued_at"]
+      end
+
+      attr_reader(
+        :flow, :client_id, :client_secret, :redirect_uris, :javascript_origins,
+        :authorization_uri, :token_credential_uri, :access_token,
+        :refresh_token, :id_token, :expires_in, :expires_at, :issued_at
+      )
+
+      def to_json
+        return MultiJson.encode({
+          self.flow => ({
+            'client_id' => self.client_id,
+            'client_secret' => self.client_secret,
+            'redirect_uris' => self.redirect_uris,
+            'javascript_origins' => self.javascript_origins,
+            'auth_uri' => self.authorization_uri,
+            'token_uri' => self.token_credential_uri,
+            'access_token' => self.access_token,
+            'refresh_token' => self.refresh_token,
+            'id_token' => self.id_token,
+            'expires_in' => self.expires_in,
+            'expires_at' => self.expires_at,
+            'issued_at' => self.issued_at
+          }).inject({}) do |accu, (k, v)|
+            # Prunes empty values from JSON output.
+            unless v == nil || (v.respond_to?(:empty?) && v.empty?)
+              accu[k] = v
+            end
+            accu
+          end
+        })
+      end
+    end
+  end
+end