diff --git a/bison/__version__.py b/bison/__version__.py
index 00bf193..c103b42 100644
--- a/bison/__version__.py
+++ b/bison/__version__.py
@@ -3,7 +3,7 @@
 __title__ = 'bison'
 __description__ = 'Python application configuration'
 __url__ = 'https://github.com/edaniszewski/bison'
-__version__ = '0.1.0'
+__version__ = '0.1.1'
 __author__ = 'Erick Daniszewski'
 __author_email__ = 'edaniszewski@gmail.com'
 __license__ = 'MIT'
diff --git a/bison/bison.py b/bison/bison.py
index 445f61e..40fd1c3 100644
--- a/bison/bison.py
+++ b/bison/bison.py
@@ -75,6 +75,11 @@ class Bison(object):
         # the unified configuration.
         self._full_config = None
 
+    def __getitem__(self, item):
+        # Set __getitem__ so the Bison config can be accessed via subscripting,
+        # e.g. config['foo']
+        return self.get(item)
+
     @property
     def config(self):
         """Get the complete configuration where the default, config,
diff --git a/bison/scheme.py b/bison/scheme.py
index df7c77a..a07a05f 100644
--- a/bison/scheme.py
+++ b/bison/scheme.py
@@ -119,8 +119,9 @@ class Scheme(object):
             # the option does not exist in the config
             else:
                 # if the option is not required, then it is fine to omit.
-                # otherwise, its omission constitutes a validation error.
-                if arg.required:
+                # otherwise, its omission constitutes a validation error unless
+                # a default value is specified for the option.
+                if arg.required and isinstance(arg.default, NoDefault):
                     raise errors.SchemeValidationError(
                         'Option "{}" is required, but not found.'.format(arg.name)
                     )
diff --git a/tests/test_bison.py b/tests/test_bison.py
index e6e4830..526663b 100644
--- a/tests/test_bison.py
+++ b/tests/test_bison.py
@@ -81,6 +81,24 @@ class TestBison:
         value = b.get(key, default=default)
         assert value == expected
 
+    @pytest.mark.parametrize(
+        'key,expected,config', [
+            ('foo', None, None),
+            ('foo', None, bison.DotDict()),
+            ('foo', None, bison.DotDict({'foo': None})),
+            ('foo', 'bar', bison.DotDict({'foo': 'bar'})),
+            ('foo.bar', 'baz', bison.DotDict({'foo': {'bar': 'baz'}})),
+            ('foo.bar.baz', 1, bison.DotDict({'foo': {'bar': {'baz': 1}}})),
+        ]
+    )
+    def test_get_subscriptable(self, key, expected, config):
+        """Get config values from Bison via subscripting."""
+        b = bison.Bison()
+        b._full_config = config  # for the test, set the config manually
+
+        value = b[key]
+        assert value == expected
+
     @pytest.mark.parametrize(
         'key,value', [
             ('foo', 'bar'),
diff --git a/tests/test_scheme.py b/tests/test_scheme.py
index 95a7630..69a13b9 100644
--- a/tests/test_scheme.py
+++ b/tests/test_scheme.py
@@ -760,3 +760,41 @@ class TestScheme:
         sch = scheme.Scheme()
         with pytest.raises(errors.SchemeValidationError):
             sch.validate(value)
+
+    @pytest.mark.parametrize(
+        'args,value', [
+            (
+                    # option does not exist in config, has default, not required
+                    (scheme.Option('foo', default='bar'),),
+                    {}
+            ),
+            (
+                    # option does not exist in config, has default, not required
+                    (
+                            scheme.DictOption('foo', scheme=scheme.Scheme(
+                                scheme.Option('bar', default=1),
+                                scheme.Option('baz'),
+                            )),
+                    ),
+                    {'foo': {'baz': 2}}
+            ),
+            (
+                    # option does not exist in config, has default, not required
+                    (
+                            scheme.ListOption('foo', member_scheme=scheme.Scheme(
+                                scheme.Option('bar', default=1),
+                                scheme.Option('baz'),
+                            )),
+                    ),
+                    {'foo': [{'baz': 2}, {'bar': 3, 'baz': 2}]}
+            ),
+        ]
+    )
+    def test_validate_has_default(self, args, value):
+        """Validate a Scheme where a default value is set, and the required field
+        may or may not be set.
+
+        If a default value is provided, it should be assumed to not be required.
+        """
+        sch = scheme.Scheme(*args)
+        sch.validate(value)