diff --git a/python_jsonschema_objects/__init__.py b/python_jsonschema_objects/__init__.py
index af24cad..c48747f 100644
--- a/python_jsonschema_objects/__init__.py
+++ b/python_jsonschema_objects/__init__.py
@@ -1,8 +1,10 @@
 import jsonschema
 from jsonschema import Draft4Validator
 from jsonschema.compat import iteritems
+import re
 import json
 import codecs
+import warnings
 import copy
 import os.path
 import inflection
@@ -22,6 +24,11 @@ __all__ = ["ObjectBuilder", "markdown_support", "ValidationError"]
 
 FILE = __file__
 
+SUPPORTED_VERSIONS = (
+    "http://json-schema.org/draft-03/schema",
+    "http://json-schema.org/draft-04/schema",
+)
+
 
 class ObjectBuilder(object):
     def __init__(self, schema_uri, resolved={}, resolver=None, validatorClass=None):
@@ -37,6 +44,17 @@ class ObjectBuilder(object):
             uri = os.path.normpath(FILE)
             self.basedir = os.path.dirname(uri)
 
+        if (
+            "$schema" in self.schema
+            and self.schema["$schema"] not in SUPPORTED_VERSIONS
+        ):
+            warnings.warn(
+                "Schema version {} not recognized. Some "
+                "keywords and features may not be supported.".format(
+                    self.schema["$schema"]
+                )
+            )
+
         self.resolver = resolver or jsonschema.RefResolver.from_schema(self.schema)
         self.resolver.handlers.update(
             {"file": self.relative_file_resolver, "memory": self.memory_resolver}
diff --git a/python_jsonschema_objects/examples/README.md b/python_jsonschema_objects/examples/README.md
index 5b0597a..8a359cf 100644
--- a/python_jsonschema_objects/examples/README.md
+++ b/python_jsonschema_objects/examples/README.md
@@ -1,10 +1,10 @@
 [![Build Status](https://travis-ci.org/cwacek/python-jsonschema-objects.svg?branch=master)](https://travis-ci.org/cwacek/python-jsonschema-objects)
-[![Reviewed by Hound](https://img.shields.io/badge/Reviewed_by-Hound-8E64B0.svg)](https://houndci.com)
 
 ## What
 
 python-jsonschema-objects provides an *automatic* class-based
-binding to JSON Schemas (draft-4 only) for use in python.
+binding to JSON Schemas for use in python. See [Draft Schema
+Support](#draft-schema-support) to see supported keywords
 
 For example, given the following schema:
 
@@ -400,8 +400,30 @@ schemas are unique.
 Tests are managed using the excellent Tox. Simply `pip install
 tox`, then `tox`.
 
+## Draft Keyword Support
+
+Most of draft-4 is supported, so only exceptions are noted
+in the table. Where a keyword functionality changed between
+drafts, the version that is supported is noted.
+
+The library will warn (but not throw an exception) if you give
+it an unsupported `$schema`
+
+| Keyword | supported | version |
+| --------| -----------| --------- |
+| $id     | true   | draft-6      |
+| propertyNames | false   | |
+| contains    | false   | |
+| const | false   |      |
+| required | true   | draft-4 |
+| examples | false |       |
+| format | false |       |
+
+
 ## Changelog
 
+*Please refer to Github releases for up to date changelogs.*
+
 **0.0.18**
 
 + Fix assignment to schemas defined using 'oneOf'

Detail JSON Schema draft version support
It doesn't look like you detail the draft version of JSON Schema you support.
Could you add this detial to the read-me please?

draft-7 is latest, but draft-8 is coming pretty soon.
diff --git a/test/test_pytest.py b/test/test_pytest.py
index d36cdf6..415101d 100644
--- a/test/test_pytest.py
+++ b/test/test_pytest.py
@@ -1,5 +1,6 @@
 import pytest
 
+import warnings
 import json
 import six
 import jsonschema
@@ -10,6 +11,29 @@ import logging
 logging.basicConfig(level=logging.DEBUG)
 
 
+@pytest.mark.parametrize(
+    "version, warn",
+    [
+        ("http://json-schema.org/schema#", True),
+        ("http://json-schema.org/draft-03/schema", False),
+        ("http://json-schema.org/draft-04/schema", False),
+        ("http://json-schema.org/draft-06/schema", True),
+        ("http://json-schema.org/draft-07/schema", True),
+    ],
+)
+def test_warnings_on_schema_version(version, warn):
+    schema = {"$schema": version, "$id": "test", "type": "object", "properties": {}}
+
+    with warnings.catch_warnings(record=True) as w:
+        pjs.ObjectBuilder(schema)
+
+        if warn:
+            assert len(w) == 1
+            assert "Schema version %s not recognized" % version in str(w[-1].message)
+        else:
+            assert len(w) == 0, w[-1].message
+
+
 def test_schema_validation():
     """ Test that the ObjectBuilder validates the schema itself.
     """
@@ -18,7 +42,7 @@ def test_schema_validation():
         "$id": "test",
         "type": "object",
         "properties": {
-            "name": "string",
+            "name": "string",  #  <-- this is invalid
             "email": {"oneOf": [{"type": "string"}, {"type": "integer"}]},
         },
         "required": ["email"],

pip install -e .[dev]
parse_log_pytest
pytest
pytest
3.6
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
attrs @ file:///opt/conda/conda-bld/attrs_1642510447205/work
certifi==2021.5.30
importlib-metadata @ file:///tmp/build/80754af9/importlib-metadata_1631916693255/work
inflection==0.5.1
iniconfig @ file:///home/linux1/recipes/ci/iniconfig_1610983019677/work
jsonschema==3.2.0
Markdown==3.3.7
more-itertools @ file:///tmp/build/80754af9/more-itertools_1637733554872/work
packaging @ file:///tmp/build/80754af9/packaging_1637314298585/work
pluggy @ file:///tmp/build/80754af9/pluggy_1615976315926/work
py @ file:///opt/conda/conda-bld/py_1644396412707/work
pyparsing @ file:///tmp/build/80754af9/pyparsing_1635766073266/work
pyrsistent==0.18.0
pytest==6.2.4
-e git+https://github.com/cwacek/python-jsonschema-objects.git@0c3ca1d7443b40052d10daf7f3384e61c29439bd#egg=python_jsonschema_objects
six==1.17.0
toml @ file:///tmp/build/80754af9/toml_1616166611790/work
typing_extensions @ file:///opt/conda/conda-bld/typing_extensions_1647553014482/work
zipp @ file:///tmp/build/80754af9/zipp_1633618647012/work

name: python-jsonschema-objects
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - attrs=21.4.0=pyhd3eb1b0_0
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2021.5.30=py36h06a4308_0
  - importlib-metadata=4.8.1=py36h06a4308_0
  - importlib_metadata=4.8.1=hd3eb1b0_0
  - iniconfig=1.1.1=pyhd3eb1b0_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.3=he6710b0_2
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - more-itertools=8.12.0=pyhd3eb1b0_0
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - packaging=21.3=pyhd3eb1b0_0
  - pip=21.2.2=py36h06a4308_0
  - pluggy=0.13.1=py36h06a4308_0
  - py=1.11.0=pyhd3eb1b0_0
  - pyparsing=3.0.4=pyhd3eb1b0_0
  - pytest=6.2.4=py36h06a4308_2
  - python=3.6.13=h12debd9_1
  - readline=8.2=h5eee18b_0
  - setuptools=58.0.4=py36h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - toml=0.10.2=pyhd3eb1b0_0
  - typing_extensions=4.1.1=pyh06a4308_0
  - wheel=0.37.1=pyhd3eb1b0_0
  - xz=5.6.4=h5eee18b_1
  - zipp=3.6.0=pyhd3eb1b0_0
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - inflection==0.5.1
      - jsonschema==3.2.0
      - markdown==3.3.7
      - pyrsistent==0.18.0
      - six==1.17.0
prefix: /opt/conda/envs/python-jsonschema-objects

test/test_pytest.py::test_warnings_on_schema_version[http://json-schema.org/schema#-True] test/test_pytest.py::test_warnings_on_schema_version[http://json-schema.org/draft-06/schema-True] test/test_pytest.py::test_warnings_on_schema_version[http://json-schema.org/draft-07/schema-True]
test/test_pytest.py::test_warnings_on_schema_version[http://json-schema.org/draft-03/schema-False] test/test_pytest.py::test_warnings_on_schema_version[http://json-schema.org/draft-04/schema-False] test/test_pytest.py::test_schema_validation test/test_pytest.py::test_regression_9 test/test_pytest.py::test_build_classes_is_idempotent test/test_pytest.py::test_underscore_properties test/test_pytest.py::test_array_regressions test/test_pytest.py::test_arrays_can_have_reffed_items_of_mixed_type test/test_pytest.py::test_regression_39 test/test_pytest.py::test_loads_markdown_schema_extraction test/test_pytest.py::test_object_builder_loads_memory_references test/test_pytest.py::test_object_builder_reads_all_definitions test/test_pytest.py::test_oneOf_validates_against_any_valid[{"MyData": test/test_pytest.py::test_oneOf_fails_against_non_matching test/test_pytest.py::test_oneOfBare_validates_against_any_valid[{"MyAddress": test/test_pytest.py::test_oneOfBare_validates_against_any_valid[{"firstName": test/test_pytest.py::test_oneOfBare_fails_against_non_matching test/test_pytest.py::test_additional_props_allowed_by_default test/test_pytest.py::test_additional_props_permitted_explicitly test/test_pytest.py::test_still_raises_when_accessing_undefined_attrs test/test_pytest.py::test_permits_deletion_of_additional_properties test/test_pytest.py::test_additional_props_disallowed_explicitly test/test_pytest.py::test_objects_can_be_empty test/test_pytest.py::test_object_equality_should_compare_data test/test_pytest.py::test_object_allows_attributes_in_oncstructor test/test_pytest.py::test_object_validates_on_json_decode test/test_pytest.py::test_object_validates_enumerations test/test_pytest.py::test_validation_of_mixed_type_enums test/test_pytest.py::test_objects_allow_non_required_attrs_to_be_missing test/test_pytest.py::test_objects_require_required_attrs_on_validate test/test_pytest.py::test_attribute_access_via_dict test/test_pytest.py::test_attribute_set_via_dict test/test_pytest.py::test_numeric_attribute_validation test/test_pytest.py::test_objects_validate_prior_to_serializing test/test_pytest.py::test_serializing_removes_null_objects test/test_pytest.py::test_lists_get_serialized_correctly test/test_pytest.py::test_dictionary_transformation[pdict0] test/test_pytest.py::test_dictionary_transformation[pdict1] test/test_pytest.py::test_strict_mode test/test_pytest.py::test_boolean_in_child_object test/test_pytest.py::test_default_values[{"type":
python_jsonschema_objects/examples/README.md python_jsonschema_objects/__init__.py
python_jsonschema_objects/examples/README.md python_jsonschema_objects/__init__.py