diff --git a/shflags b/shflags
index 5cfab3b..1b7748a 100644
--- a/shflags
+++ b/shflags
@@ -871,7 +871,7 @@ _flags_parseGetopt() {
         ;;
 
       ${__FLAGS_TYPE_STRING})
-        eval "FLAGS_${_flags_usName_}='${_flags_arg_}'"
+        eval "FLAGS_${_flags_usName_}=\${_flags_arg_}"
         ;;
     esac
 
@@ -894,7 +894,7 @@ _flags_parseGetopt() {
   # Give user back non-flag arguments.
   FLAGS_ARGV=''
   while [ $# -gt 0 ]; do
-    FLAGS_ARGV="${FLAGS_ARGV:+${FLAGS_ARGV} }'$1'"
+    FLAGS_ARGV="${FLAGS_ARGV:+${FLAGS_ARGV} } `_flags_escape "$1"`"
     shift
   done
 
@@ -903,6 +903,13 @@ _flags_parseGetopt() {
   return ${flags_return}
 }
 
+_flags_escape() {
+    [ -n "${BASH_VERSION:-}" ] && printf "%q\n" "$1" && return 0
+    [ -n "${ZSH_VERSION:-}" ]&& printf "%q\n" "$1" && return 0
+    [ -n "${KSH_VERSION:-}" ]&& printf "%q\n" "$1" && return 0
+    printf "%s\n" "$1" | sed -e "s/'/'\"'\"'/g" -e "1s/^/'/" -e "\$s/\$/'/"
+}
+
 # Perform some path using built-ins.
 #
 # Args:
diff --git a/shflags_parsing_quotes_test.sh b/shflags_parsing_quotes_test.sh
new file mode 100755
index 0000000..fc017ef
--- /dev/null
+++ b/shflags_parsing_quotes_test.sh
@@ -0,0 +1,99 @@
+#! /bin/sh
+# vim:et:ft=sh:sts=2:sw=2
+#
+# shFlags unit test for the flag definition methods
+#
+# Copyright 2008-2017 Kate Ward. All Rights Reserved.
+# Released under the Apache 2.0 license.
+#
+# Author: kate.ward@forestent.com (Kate Ward)
+# https://github.com/kward/shflags
+#
+### ShellCheck (http://www.shellcheck.net/)
+# Disable source following.
+#   shellcheck disable=SC1090,SC1091
+
+# TODO(kward): assert on FLAGS errors
+# TODO(kward): testNonStandardIFS()
+
+# Exit immediately if a pipeline or subshell exits with a non-zero status.
+#set -e
+
+# Treat unset variables as an error.
+set -u
+
+# These variables will be overridden by the test helpers.
+returnF="${TMPDIR:-/tmp}/return"
+stdoutF="${TMPDIR:-/tmp}/STDOUT"
+stderrF="${TMPDIR:-/tmp}/STDERR"
+
+# Load test helpers.
+. ./shflags_test_helpers
+
+testOptionStringsWithQuotes() {
+    _testValidOptionStrings -s "Single Quote Flag's Test"
+    _testValidOptionStrings -s "Double Quote \"Flag\" Test"
+    _testValidOptionStrings -s "Mixed Quote's \"Flag\" Test"
+    _testValidOptionStrings -s 'Mixed Quote'\''s "Flag" Test'
+}
+
+testArgumentStringsWithQuotes() {
+    _testValidArgumentStrings "Single Quote Flag's Test"
+    _testValidArgumentStrings "Double Quote \"Flag\" Test"
+    _testValidArgumentStrings "Mixed Quote's \"Flag\" Test"
+}
+
+_testValidOptionStrings() {
+    flag=$1
+    value=$2
+
+    FLAGS "${flag}" "${value}" >"${stdoutF}" 2>"${stderrF}"
+    r3turn=$?
+    assertTrue "'FLAGS ${flag} ${value}' returned a non-zero result (${r3turn})" \
+        ${r3turn}
+    # shellcheck disable=SC2154
+    assertEquals "string (${value}) test failed." "${value}" "${FLAGS_str}"
+    if [ ${r3turn} -eq "${FLAGS_TRUE}" ]; then
+        assertFalse 'expected no output to STDERR' "[ -s '${stderrF}' ]"
+    else
+        # Validate that an error is thrown for unsupported getopt uses.
+        assertFatalMsg '.* spaces in options'
+    fi
+    th_showOutput ${r3turn} "${stdoutF}" "${stderrF}"
+}
+
+_testValidArgumentStrings() {
+    quoted_string="$1"
+    FLAGS "$quoted_string" >"${stdoutF}" 2>"${stderrF}"
+    r3turn=$?
+    assertTrue "'FLAGS $quoted_string' returned a non-zero result (${r3turn})" \
+        ${r3turn}
+    eval set -- "${FLAGS_ARGV}"
+    assertEquals "$quoted_string" "$1"
+}
+
+oneTimeSetUp() {
+    th_oneTimeSetUp
+
+    if flags_getoptIsStd; then
+        th_warn 'Standard version of getopt found. Enhanced tests will be skipped.'
+    else
+        th_warn 'Enhanced version of getopt found. Standard tests will be skipped.'
+    fi
+}
+
+setUp() {
+    DEFINE_boolean bool false 'boolean test' 'b'
+    DEFINE_float float 0.0 'float test' 'f'
+    DEFINE_integer int 0 'integer test' 'i'
+    DEFINE_string str '' 'string test' 's'
+}
+
+tearDown() {
+    flags_reset
+}
+
+# Load and run shUnit2.
+# shellcheck disable=SC2034
+[ -n "${ZSH_VERSION:-}" ] && SHUNIT_PARENT=$0
+. "${TH_SHUNIT}"