diff --git a/javascript/README b/javascript/README
index e40da42dd..9809c8530 100644
--- a/javascript/README
+++ b/javascript/README
@@ -51,6 +51,10 @@ project:
       PhoneNumberUtilTest.java => phonenumberutil_test.js
       AsYouTypeFormatterTest.java => asyoutypeformatter_test.js
 
+4.  Run the Closure Compiler to get your changes syntax checked:
+
+    ./compile.sh
+
 
 TODO:
 =====
diff --git a/javascript/compile.sh b/javascript/compile.sh
new file mode 100755
index 000000000..e39b3be54
--- /dev/null
+++ b/javascript/compile.sh
@@ -0,0 +1,93 @@
+#! /bin/sh
+
+# Copyright (C) 2012 The Libphonenumber Authors
+#
+# 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.
+
+# Author: Fredrik Roubert
+
+# Compiles the Javascript implementation of libphonenumber, using the Google
+# Closure Compiler.
+#
+# The environment variable CLASSPATH is used to provide the location of the
+# Closure Compiler JAR (compiler.jar), and the environment variable CLOSUREPATH
+# is used to provide the root directory of the Closure library source files. If
+# the defaults don't work for your system, override them on the command line,
+# for example like this:
+#
+# CLASSPATH=/opt/closure-compiler/compiler.jar ./compile.sh
+
+: ${CLASSPATH:='/usr/local/share/closure-compiler/compiler.jar'}
+: ${CLOSUREPATH:='../../closure-library/closure/goog'}
+
+# If CLASSPATH was set by this script, it needs to be exported to make it
+# visible to the JVM.
+export CLASSPATH
+
+SRCPATH='i18n/phonenumbers'
+
+function jscomp {
+  java com.google.javascript.jscomp.CommandLineRunner \
+    --jscomp_warning=deprecated \
+    --jscomp_warning=missingProperties \
+    --js $CLOSUREPATH/base.js \
+    --js $CLOSUREPATH/array/array.js \
+    --js $CLOSUREPATH/asserts/asserts.js \
+    --js $CLOSUREPATH/debug/error.js \
+    --js $CLOSUREPATH/object/object.js \
+    --js $CLOSUREPATH/proto2/descriptor.js \
+    --js $CLOSUREPATH/proto2/fielddescriptor.js \
+    --js $CLOSUREPATH/proto2/lazydeserializer.js \
+    --js $CLOSUREPATH/proto2/message.js \
+    --js $CLOSUREPATH/proto2/pbliteserializer.js \
+    --js $CLOSUREPATH/proto2/serializer.js \
+    --js $CLOSUREPATH/proto2/util.js \
+    --js $CLOSUREPATH/string/string.js \
+    --js $CLOSUREPATH/string/stringbuffer.js \
+    "$@"
+}
+
+echo 'Compiling with regular metadata...'
+
+jscomp \
+  --js $SRCPATH/asyoutypeformatter.js \
+  --js $SRCPATH/metadata.js \
+  --js $SRCPATH/phonemetadata.pb.js \
+  --js $SRCPATH/phonenumber.pb.js \
+  --js $SRCPATH/phonenumberutil.js \
+  --js_output_file=libphonenumber-compiled.js \
+  --output_manifest=libphonenumber-compiled.MF
+
+echo 'Compiling with lite metadata...'
+
+jscomp \
+  --js $SRCPATH/asyoutypeformatter.js \
+  --js $SRCPATH/metadatalite.js \
+  --js $SRCPATH/phonemetadata.pb.js \
+  --js $SRCPATH/phonenumber.pb.js \
+  --js $SRCPATH/phonenumberutil.js \
+  --js_output_file=libphonenumber-lite-compiled.js \
+  --output_manifest=libphonenumber-lite-compiled.MF
+
+echo 'Compiling with metadata for testing...'
+
+jscomp \
+  --js $SRCPATH/asyoutypeformatter.js \
+  --js $SRCPATH/metadatafortesting.js \
+  --js $SRCPATH/phonemetadata.pb.js \
+  --js $SRCPATH/phonenumber.pb.js \
+  --js $SRCPATH/phonenumberutil.js \
+  --js_output_file=libphonenumber-testing-compiled.js \
+  --output_manifest=libphonenumber-testing-compiled.MF
+
+echo 'Done.'