diff --git a/tests/rules/test_quoted_strings.py b/tests/rules/test_quoted_strings.py
index 973660c..0fdba71 100644
--- a/tests/rules/test_quoted_strings.py
+++ b/tests/rules/test_quoted_strings.py
@@ -22,6 +22,7 @@ class QuotedTestCase(RuleTestCase):
 
     def test_disabled(self):
         conf = 'quoted-strings: disable'
+
         self.check('---\n'
                    'foo: bar\n', conf)
         self.check('---\n'
@@ -35,18 +36,18 @@ class QuotedTestCase(RuleTestCase):
 
     def test_quote_type_any(self):
         conf = 'quoted-strings: {quote-type: any}\n'
+
         self.check('---\n'
                    'boolean1: true\n'
                    'number1: 123\n'
                    'string1: foo\n'                          # fails
-                   'string2: "true"\n'
-                   'string3: "123"\n'
-                   'string4: \'true\'\n'
-                   'string5: "foo"\n'
-                   'string6: \'bar\'\n'
-                   'string7: !!str genericstring\n'
-                   'string8: !!str 456\n'
-                   'string9: !!str "quotedgenericstring"\n'
+                   'string2: "foo"\n'
+                   'string3: "true"\n'
+                   'string4: "123"\n'
+                   'string5: \'bar\'\n'
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
                    'binary: !!binary binstring\n'
                    'integer: !!int intstring\n'
                    'boolean2: !!bool boolstring\n'
@@ -60,7 +61,7 @@ class QuotedTestCase(RuleTestCase):
                    '  word 1\n'
                    '  word 2\n'
                    'multiline string 3:\n'
-                   '  word 1\n'
+                   '  word 1\n'               # fails
                    '  word 2\n'
                    'multiline string 4:\n'
                    '  "word 1\\\n'
@@ -69,6 +70,7 @@ class QuotedTestCase(RuleTestCase):
 
     def test_quote_type_single(self):
         conf = 'quoted-strings: {quote-type: single}\n'
+
         self.check('---\n'
                    'boolean1: true\n'
                    'number1: 123\n'
@@ -94,7 +96,7 @@ class QuotedTestCase(RuleTestCase):
                    '  word 1\n'
                    '  word 2\n'
                    'multiline string 3:\n'
-                   '  word 1\n'
+                   '  word 1\n'               # fails
                    '  word 2\n'
                    'multiline string 4:\n'
                    '  "word 1\\\n'
@@ -103,13 +105,83 @@ class QuotedTestCase(RuleTestCase):
 
     def test_quote_type_double(self):
         conf = 'quoted-strings: {quote-type: double}\n'
+
         self.check('---\n'
                    'boolean1: true\n'
                    'number1: 123\n'
                    'string1: foo\n'                          # fails
                    'string2: "foo"\n'
-                   'string3: \'true\'\n'                     # fails
-                   'string4: \'123\'\n'                      # fails
+                   'string3: "true"\n'
+                   'string4: "123"\n'
+                   'string5: \'bar\'\n'                      # fails
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
+                   'binary: !!binary binstring\n'
+                   'integer: !!int intstring\n'
+                   'boolean2: !!bool boolstring\n'
+                   'boolean3: !!bool "quotedboolstring"\n',
+                   conf, problem1=(4, 10), problem2=(8, 10))
+        self.check('---\n'
+                   'multiline string 1: |\n'
+                   '  line 1\n'
+                   '  line 2\n'
+                   'multiline string 2: >\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 3:\n'
+                   '  word 1\n'               # fails
+                   '  word 2\n'
+                   'multiline string 4:\n'
+                   '  "word 1\\\n'
+                   '   word 2"\n',
+                   conf, problem1=(9, 3))
+
+    def test_disallow_redundant_quotes(self):
+        conf = 'quoted-strings: {required: only-when-needed}\n'
+
+        self.check('---\n'
+                   'boolean1: true\n'
+                   'number1: 123\n'
+                   'string1: foo\n'
+                   'string2: "foo"\n'                        # fails
+                   'string3: "true"\n'
+                   'string4: "123"\n'
+                   'string5: \'bar\'\n'                      # fails
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
+                   'binary: !!binary binstring\n'
+                   'integer: !!int intstring\n'
+                   'boolean2: !!bool boolstring\n'
+                   'boolean3: !!bool "quotedboolstring"\n',
+                   conf, problem1=(5, 10), problem2=(8, 10))
+        self.check('---\n'
+                   'multiline string 1: |\n'
+                   '  line 1\n'
+                   '  line 2\n'
+                   'multiline string 2: >\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 3:\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 4:\n'
+                   '  "word 1\\\n'            # fails
+                   '   word 2"\n',
+                   conf, problem1=(12, 3))
+
+    def test_disallow_redundant_single_quotes(self):
+        conf = 'quoted-strings: {quote-type: single, ' + \
+                                'required: only-when-needed}\n'
+
+        self.check('---\n'
+                   'boolean1: true\n'
+                   'number1: 123\n'
+                   'string1: foo\n'
+                   'string2: "foo"\n'                        # fails
+                   'string3: "true"\n'                       # fails
+                   'string4: "123"\n'                        # fails
                    'string5: \'bar\'\n'                      # fails
                    'string6: !!str genericstring\n'
                    'string7: !!str 456\n'
@@ -118,7 +190,7 @@ class QuotedTestCase(RuleTestCase):
                    'integer: !!int intstring\n'
                    'boolean2: !!bool boolstring\n'
                    'boolean3: !!bool "quotedboolstring"\n',
-                   conf, problem1=(4, 10), problem2=(6, 10),
+                   conf, problem1=(5, 10), problem2=(6, 10),
                    problem3=(7, 10), problem4=(8, 10))
         self.check('---\n'
                    'multiline string 1: |\n'
@@ -131,6 +203,144 @@ class QuotedTestCase(RuleTestCase):
                    '  word 1\n'
                    '  word 2\n'
                    'multiline string 4:\n'
+                   '  "word 1\\\n'            # fails
+                   '   word 2"\n',
+                   conf, problem1=(12, 3))
+
+    def test_single_quotes_required(self):
+        conf = 'quoted-strings: {quote-type: single, required: true}\n'
+
+        self.check('---\n'
+                   'boolean1: true\n'
+                   'number1: 123\n'
+                   'string1: foo\n'                          # fails
+                   'string2: "foo"\n'                        # fails
+                   'string3: "true"\n'                       # fails
+                   'string4: "123"\n'                        # fails
+                   'string5: \'bar\'\n'
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
+                   'binary: !!binary binstring\n'
+                   'integer: !!int intstring\n'
+                   'boolean2: !!bool boolstring\n'
+                   'boolean3: !!bool "quotedboolstring"\n',
+                   conf, problem1=(4, 10), problem2=(5, 10),
+                   problem3=(6, 10), problem4=(7, 10))
+        self.check('---\n'
+                   'multiline string 1: |\n'
+                   '  line 1\n'
+                   '  line 2\n'
+                   'multiline string 2: >\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 3:\n'
+                   '  word 1\n'               # fails
+                   '  word 2\n'
+                   'multiline string 4:\n'
+                   '  "word 1\\\n'            # fails
+                   '   word 2"\n',
+                   conf, problem1=(9, 3), problem2=(12, 3))
+
+    def test_any_quotes_relaxed(self):
+        conf = 'quoted-strings: {quote-type: any, required: false}\n'
+
+        self.check('---\n'
+                   'boolean1: true\n'
+                   'number1: 123\n'
+                   'string1: foo\n'
+                   'string2: "foo"\n'
+                   'string3: "true"\n'
+                   'string4: "123"\n'
+                   'string5: \'bar\'\n'
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
+                   'binary: !!binary binstring\n'
+                   'integer: !!int intstring\n'
+                   'boolean2: !!bool boolstring\n'
+                   'boolean3: !!bool "quotedboolstring"\n',
+                   conf)
+        self.check('---\n'
+                   'multiline string 1: |\n'
+                   '  line 1\n'
+                   '  line 2\n'
+                   'multiline string 2: >\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 3:\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 4:\n'
+                   '  "word 1\\\n'
+                   '   word 2"\n',
+                   conf)
+
+    def test_single_quotes_relaxed(self):
+        conf = 'quoted-strings: {quote-type: single, required: false}\n'
+
+        self.check('---\n'
+                   'boolean1: true\n'
+                   'number1: 123\n'
+                   'string1: foo\n'
+                   'string2: "foo"\n'                        # fails
+                   'string3: "true"\n'                       # fails
+                   'string4: "123"\n'                        # fails
+                   'string5: \'bar\'\n'
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
+                   'binary: !!binary binstring\n'
+                   'integer: !!int intstring\n'
+                   'boolean2: !!bool boolstring\n'
+                   'boolean3: !!bool "quotedboolstring"\n',
+                   conf, problem2=(5, 10),
+                   problem3=(6, 10), problem4=(7, 10))
+        self.check('---\n'
+                   'multiline string 1: |\n'
+                   '  line 1\n'
+                   '  line 2\n'
+                   'multiline string 2: >\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 3:\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 4:\n'
+                   '  "word 1\\\n'            # fails
+                   '   word 2"\n',
+                   conf, problem1=(12, 3))
+
+    def test_quotes_required(self):
+        conf = 'quoted-strings: {quote-type: any, required: true}\n'
+
+        self.check('---\n'
+                   'boolean1: true\n'
+                   'number1: 123\n'
+                   'string1: foo\n'                          # fails
+                   'string2: "foo"\n'
+                   'string3: "true"\n'
+                   'string4: "123"\n'
+                   'string5: \'bar\'\n'
+                   'string6: !!str genericstring\n'
+                   'string7: !!str 456\n'
+                   'string8: !!str "quotedgenericstring"\n'
+                   'binary: !!binary binstring\n'
+                   'integer: !!int intstring\n'
+                   'boolean2: !!bool boolstring\n'
+                   'boolean3: !!bool "quotedboolstring"\n',
+                   conf, problem2=(4, 10))
+        self.check('---\n'
+                   'multiline string 1: |\n'
+                   '  line 1\n'
+                   '  line 2\n'
+                   'multiline string 2: >\n'
+                   '  word 1\n'
+                   '  word 2\n'
+                   'multiline string 3:\n'
+                   '  word 1\n'               # fails
+                   '  word 2\n'
+                   'multiline string 4:\n'
                    '  "word 1\\\n'
                    '   word 2"\n',
                    conf, problem1=(9, 3))
diff --git a/yamllint/rules/quoted_strings.py b/yamllint/rules/quoted_strings.py
index 4fc5aa2..aaa635d 100644
--- a/yamllint/rules/quoted_strings.py
+++ b/yamllint/rules/quoted_strings.py
@@ -15,15 +15,23 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
-Use this rule to forbid any string values that are not quoted.
-You can also enforce the type of the quote used using the ``quote-type`` option
-(``single``, ``double`` or ``any``).
+Use this rule to forbid any string values that are not quoted, or to prevent
+quoted strings without needing it. You can also enforce the type of the quote
+used.
+
+.. rubric:: Options
+
+* ``quote-type`` defines allowed quotes: ``single``, ``double`` or ``any``
+  (default).
+* ``required`` defines whether using quotes in string values is required
+  (``true``, default) or not (``false``), or only allowed when really needed
+  (``only-when-needed``).
 
 **Note**: Multi-line strings (with ``|`` or ``>``) will not be checked.
 
 .. rubric:: Examples
 
-#. With ``quoted-strings: {quote-type: any}``
+#. With ``quoted-strings: {quote-type: any, required: true}``
 
    the following code snippet would **PASS**:
    ::
@@ -37,6 +45,24 @@ You can also enforce the type of the quote used using the ``quote-type`` option
    ::
 
     foo: bar
+
+#. With ``quoted-strings: {quote-type: single, required: only-when-needed}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    foo: bar
+    bar: foo
+    not_number: '123'
+    not_boolean: 'true'
+    not_comment: '# comment'
+    not_list: '[1, 2, 3]'
+    not_map: '{a: 1, b: 2}'
+
+   the following code snippet would **FAIL**:
+   ::
+
+    foo: 'bar'
 """
 
 import yaml
@@ -45,13 +71,23 @@ from yamllint.linter import LintProblem
 
 ID = 'quoted-strings'
 TYPE = 'token'
-CONF = {'quote-type': ('any', 'single', 'double')}
-DEFAULT = {'quote-type': 'any'}
+CONF = {'quote-type': ('any', 'single', 'double'),
+        'required': (True, False, 'only-when-needed')}
+DEFAULT = {'quote-type': 'any',
+           'required': True}
 
+DEFAULT_SCALAR_TAG = u'tag:yaml.org,2002:str'
+START_TOKENS = {'#', '*', '!', '?', '@', '`', '&',
+                ',', '-', '{', '}', '[', ']', ':'}
 
-def check(conf, token, prev, next, nextnext, context):
-    quote_type = conf['quote-type']
 
+def quote_match(quote_type, token_style):
+    return ((quote_type == 'any') or
+            (quote_type == 'single' and token_style == "'") or
+            (quote_type == 'double' and token_style == '"'))
+
+
+def check(conf, token, prev, next, nextnext, context):
     if not (isinstance(token, yaml.tokens.ScalarToken) and
             isinstance(prev, (yaml.ValueToken, yaml.TagToken))):
         return
@@ -62,20 +98,49 @@ def check(conf, token, prev, next, nextnext, context):
         return
 
     # Ignore numbers, booleans, etc.
-    if token.plain:
-        resolver = yaml.resolver.Resolver()
-        if resolver.resolve(yaml.nodes.ScalarNode, token.value,
-                            (True, False)) != 'tag:yaml.org,2002:str':
-            return
+    resolver = yaml.resolver.Resolver()
+    tag = resolver.resolve(yaml.nodes.ScalarNode, token.value, (True, False))
+    if token.plain and tag != DEFAULT_SCALAR_TAG:
+        return
 
     # Ignore multi-line strings
     if (not token.plain) and (token.style == "|" or token.style == ">"):
         return
 
-    if ((quote_type == 'single' and token.style != "'") or
-            (quote_type == 'double' and token.style != '"') or
-            (quote_type == 'any' and token.style is None)):
+    quote_type = conf['quote-type']
+    required = conf['required']
+
+    # Completely relaxed about quotes (same as the rule being disabled)
+    if required is False and quote_type == 'any':
+        return
+
+    msg = None
+    if required is True:
+
+        # Quotes are mandatory and need to match config
+        if token.style is None or not quote_match(quote_type, token.style):
+            msg = "string value is not quoted with %s quotes" % (quote_type)
+
+    elif required is False:
+
+        # Quotes are not mandatory but when used need to match config
+        if token.style and not quote_match(quote_type, token.style):
+            msg = "string value is not quoted with %s quotes" % (quote_type)
+
+    elif not token.plain:
+
+        # Quotes are disallowed when not needed
+        if (tag == DEFAULT_SCALAR_TAG and token.value
+                and token.value[0] not in START_TOKENS):
+            msg = "string value is redundantly quoted with %s quotes" % (
+                quote_type)
+
+        # But when used need to match config
+        elif token.style and not quote_match(quote_type, token.style):
+            msg = "string value is not quoted with %s quotes" % (quote_type)
+
+    if msg is not None:
         yield LintProblem(
             token.start_mark.line + 1,
             token.start_mark.column + 1,
-            "string value is not quoted with %s quotes" % (quote_type))
+            msg)