diff --git a/cms/djangoapps/contentstore/views/preview.py b/cms/djangoapps/contentstore/views/preview.py
index b64a77ddb2a7..e2fc1deaf38a 100644
--- a/cms/djangoapps/contentstore/views/preview.py
+++ b/cms/djangoapps/contentstore/views/preview.py
@@ -35,6 +35,8 @@
 from common.djangoapps.edxmako.shortcuts import render_to_string
 from common.djangoapps.edxmako.services import MakoService
 from common.djangoapps.xblock_django.user_service import DjangoXBlockUserService
+from common.lib.xmodule.xmodule.x_module import AsideKeyGenerator, OpaqueKeyReader
+from lms.djangoapps.courseware.services import ModuleService
 from lms.djangoapps.lms_xblock.field_data import LmsFieldData
 from openedx.core.lib.license import wrap_with_license
 from openedx.core.lib.cache_utils import CacheService
@@ -207,11 +209,12 @@ def _preview_module_system(request, descriptor, field_data):
         else:
             preview_anonymous_user_id = anonymous_id_for_user(request.user, course_id)
 
+    module_service = ModuleService(partial(_load_preview_module, request=request))
+
     return PreviewModuleSystem(
         static_url=settings.STATIC_URL,
         # TODO (cpennington): Do we want to track how instructors are using the preview problems?
         track_function=lambda event_type, event: None,
-        get_module=partial(_load_preview_module, request),
         debug=True,
         mixins=settings.XBLOCK_MIXINS,
         course_id=course_id,
@@ -221,7 +224,6 @@ def _preview_module_system(request, descriptor, field_data):
         wrappers_asides=wrappers_asides,
         error_descriptor_class=ErrorBlock,
         # Get the raw DescriptorSystem, not the CombinedSystem
-        descriptor_runtime=descriptor._runtime,  # pylint: disable=protected-access
         services={
             "field-data": field_data,
             "i18n": ModuleI18nService,
@@ -236,8 +238,11 @@ def _preview_module_system(request, descriptor, field_data):
             "teams_configuration": TeamsConfigurationService(),
             "sandbox": SandboxService(contentstore=contentstore, course_id=course_id),
             "cache": CacheService(cache),
-            'replace_urls': replace_url_service
+            'replace_urls': replace_url_service,
+            'module': module_service
         },
+        id_reader=getattr(descriptor._runtime, 'id_reader', OpaqueKeyReader()),  # pylint: disable=protected-access
+        id_generator=getattr(descriptor._runtime, 'id_generator', AsideKeyGenerator()),  # pylint: disable=protected-access
     )
 
 
diff --git a/cms/djangoapps/contentstore/views/tests/test_preview.py b/cms/djangoapps/contentstore/views/tests/test_preview.py
index 66e934911f06..ed476b91f887 100644
--- a/cms/djangoapps/contentstore/views/tests/test_preview.py
+++ b/cms/djangoapps/contentstore/views/tests/test_preview.py
@@ -28,7 +28,7 @@
 from common.djangoapps import static_replace
 from common.djangoapps.student.tests.factories import UserFactory
 
-from ..preview import _preview_module_system, get_preview_fragment
+from ..preview import _preview_module_system, get_preview_fragment, _load_preview_module
 
 
 @ddt.ddt
@@ -178,6 +178,7 @@ def test_block_branch_not_changed_by_preview_handler(self, default_store):
 @XBlock.needs("field-data")
 @XBlock.needs("i18n")
 @XBlock.needs("mako")
+@XBlock.needs("module")
 @XBlock.needs("replace_urls")
 @XBlock.needs("user")
 @XBlock.needs("teams_configuration")
@@ -210,7 +211,7 @@ def setUp(self):
         self.field_data = mock.Mock()
 
     @XBlock.register_temp_plugin(PureXBlock, identifier='pure')
-    @ddt.data("user", "i18n", "field-data", "teams_configuration", "replace_urls")
+    @ddt.data("user", "i18n", "field-data", "teams_configuration", "replace_urls", "module")
     def test_expected_services_exist(self, expected_service):
         """
         Tests that the 'user' and 'i18n' services are provided by the Studio runtime.
@@ -298,6 +299,9 @@ def test_replace_urls(self):
         assert self.runtime.replace_urls(html) == \
             static_replace.replace_static_urls(html, course_id=self.runtime.course_id)
 
+    def test_get_module(self):
+        assert self.runtime.get_module(self.descriptor) == _load_preview_module(self.request, self.descriptor)
+
     def test_anonymous_user_id_preview(self):
         assert self.runtime.anonymous_student_id == 'student'
 
diff --git a/common/lib/xmodule/xmodule/conditional_module.py b/common/lib/xmodule/xmodule/conditional_module.py
index 238d5564fffd..399da809b914 100644
--- a/common/lib/xmodule/xmodule/conditional_module.py
+++ b/common/lib/xmodule/xmodule/conditional_module.py
@@ -39,6 +39,7 @@
 
 
 @XBlock.needs('mako')
+@XBlock.needs('module')
 class ConditionalBlock(
     SequenceMixin,
     MakoTemplateBlockBase,
@@ -317,7 +318,8 @@ def get_required_blocks(self):
         """
         Returns a list of bound XBlocks instances upon which XBlock depends.
         """
-        return [self.system.get_module(descriptor) for descriptor in self.get_required_module_descriptors()]
+        module_service = self.runtime.service(self, 'module')
+        return [module_service.get_module(descriptor) for descriptor in self.get_required_module_descriptors()]
 
     def get_required_module_descriptors(self):
         """
diff --git a/common/lib/xmodule/xmodule/library_sourced_block.py b/common/lib/xmodule/xmodule/library_sourced_block.py
index d96741d6e447..8a917bc800c0 100644
--- a/common/lib/xmodule/xmodule/library_sourced_block.py
+++ b/common/lib/xmodule/xmodule/library_sourced_block.py
@@ -101,7 +101,13 @@ def student_view(self, context):
         Renders the view that learners see.
         """
         result = Fragment()
-        child_frags = self.runtime.render_children(self, context=context)
+
+        # TODO: uncomment this line and remove _render_children() once
+        # merger of ModuleSystem and DescriptorSystem is complete
+
+        # child_frags = self.runtime.render_children(self, context=context)
+        child_frags = self._render_children(context)
+
         result.add_resources(child_frags)
         result.add_content('<div class="library-sourced-content">')
         for frag in child_frags:
@@ -109,6 +115,26 @@ def student_view(self, context):
         result.add_content('</div>')
         return result
 
+    def _render_children(self, context):
+        """
+        Use CombinedSystem runtime to get block and render each child individually.
+
+        The runtime.render_children() method was earlier used to render each child
+        However, this caused a problem, when we removed the get_block() and
+        descriptor_runtime properties from the ModuleSystem, as the render_children
+        method ran in the context of LmsModuleSystem which is a child class of
+        ModuleSystem.
+
+        This is intended to be a temporary method until deprecation of all properties
+        of ModuleSystem and merger of ModuleSystem and DescriptorSystem is complete.
+        """
+        results = []
+        for child_id in self.children:
+            child = self.runtime.get_block(child_id)
+            result = self.runtime.render_child(child, context=context)
+            results.append(result)
+        return results
+
     def validate_field_data(self, validation, data):
         """
         Validate this block's field data. Instead of checking fields like self.name, check the
diff --git a/common/lib/xmodule/xmodule/split_test_module.py b/common/lib/xmodule/xmodule/split_test_module.py
index 069f9995481f..d269646d5c44 100644
--- a/common/lib/xmodule/xmodule/split_test_module.py
+++ b/common/lib/xmodule/xmodule/split_test_module.py
@@ -125,6 +125,7 @@ def get_split_user_partitions(user_partitions):
 @XBlock.needs('mako')
 @XBlock.needs('partitions')
 @XBlock.needs('user')
+@XBlock.needs('module')
 class SplitTestBlock(  # lint-amnesty, pylint: disable=abstract-method
     SplitTestFields,
     SequenceMixin,
@@ -192,7 +193,7 @@ def child(self):
         Return the user bound child block for the partition or None.
         """
         if self.child_descriptor is not None:
-            return self.system.get_module(self.child_descriptor)
+            return self.runtime.service(self, 'module').get_module(self.child_descriptor)
         else:
             return None
 
@@ -272,7 +273,7 @@ def _staff_view(self, context):
 
         for child_location in self.children:  # pylint: disable=no-member
             child_descriptor = self.get_child_descriptor_by_location(child_location)
-            child = self.system.get_module(child_descriptor)
+            child = self.runtime.service(self, 'module').get_module(child_descriptor)
             rendered_child = child.render(STUDENT_VIEW, context)
             fragment.add_fragment_resources(rendered_child)
             group_name, updated_group_id = self.get_data_for_vertical(child)
@@ -347,7 +348,7 @@ def studio_render_children(self, fragment, children, context):
         """
         html = ""
         for active_child_descriptor in children:
-            active_child = self.system.get_module(active_child_descriptor)
+            active_child = self.runtime.service(self, 'module').get_module(active_child_descriptor)
             rendered_child = active_child.render(StudioEditableBlock.get_preview_view_name(active_child), context)
             if active_child.category == 'vertical':
                 group_name, group_id = self.get_data_for_vertical(active_child)
diff --git a/common/lib/xmodule/xmodule/tests/__init__.py b/common/lib/xmodule/xmodule/tests/__init__.py
index fd38c6f64d45..4683b9ca3e7d 100644
--- a/common/lib/xmodule/xmodule/tests/__init__.py
+++ b/common/lib/xmodule/xmodule/tests/__init__.py
@@ -15,10 +15,11 @@
 import traceback
 import unittest
 from contextlib import contextmanager
-from functools import wraps
+from functools import partial, wraps
 from unittest.mock import Mock
 
 from django.test import TestCase
+from lms.djangoapps.courseware.services import ModuleService
 
 from opaque_keys.edx.keys import CourseKey
 from path import Path as path
@@ -152,7 +153,6 @@ def get_module(descriptor):
     return TestModuleSystem(
         static_url='/static',
         track_function=Mock(name='get_test_system.track_function'),
-        get_module=get_module,
         debug=True,
         hostname="edx.org",
         services={
@@ -166,12 +166,12 @@ def get_module(descriptor):
                 waittime=10,
                 construct_callback=Mock(name='get_test_system.xqueue.construct_callback', side_effect="/"),
             ),
-            'replace_urls': replace_url_service
+            'replace_urls': replace_url_service,
+            'module': ModuleService(partial(get_module))
         },
         node_path=os.environ.get("NODE_PATH", "/usr/local/lib/node_modules"),
         course_id=course_id,
         error_descriptor_class=ErrorBlock,
-        descriptor_runtime=descriptor_system,
     )
 
 
diff --git a/common/lib/xmodule/xmodule/tests/test_conditional.py b/common/lib/xmodule/xmodule/tests/test_conditional.py
index ac862add812c..e4831942651b 100644
--- a/common/lib/xmodule/xmodule/tests/test_conditional.py
+++ b/common/lib/xmodule/xmodule/tests/test_conditional.py
@@ -1,11 +1,13 @@
 # lint-amnesty, pylint: disable=missing-module-docstring
 
+from functools import partial
 import json
 import unittest
 from unittest.mock import Mock, patch
 
 from django.conf import settings
 from fs.memoryfs import MemoryFS
+from lms.djangoapps.courseware.services import ModuleService
 from lxml import etree
 from opaque_keys.edx.keys import CourseKey
 from opaque_keys.edx.locator import BlockUsageLocator, CourseLocator
@@ -131,9 +133,15 @@ def load_item(usage_id, for_parent=None):  # pylint: disable=unused-argument
             ScopeIds(None, None, cond_location, cond_location)
         )
         cond_descriptor.xmodule_runtime = system
-        system.get_module = lambda desc: desc if visible_to_nonstaff_users(desc) else None
+
+        def _check_module_user_access(descriptor):
+            if visible_to_nonstaff_users(descriptor):
+                return descriptor
+            return None
+
+        system._services['module'] = ModuleService(partial(_check_module_user_access))
         cond_descriptor.get_required_blocks = [
-            system.get_module(source_descriptor),
+            system._services['module'].get_module(source_descriptor),
         ]
 
         # return dict:
@@ -229,7 +237,7 @@ def setUp(self):
 
     def get_module_for_location(self, location):
         descriptor = self.modulestore.get_item(location, depth=None)
-        return self.test_system.get_module(descriptor)
+        return self.test_system._services['module'].get_module(descriptor)
 
     @patch('xmodule.x_module.descriptor_global_local_resource_url')
     @patch.dict(settings.FEATURES, {'ENABLE_EDXNOTES': False})
diff --git a/common/lib/xmodule/xmodule/tests/test_library_content.py b/common/lib/xmodule/xmodule/tests/test_library_content.py
index 628f471e88eb..a900b4c0fe03 100644
--- a/common/lib/xmodule/xmodule/tests/test_library_content.py
+++ b/common/lib/xmodule/xmodule/tests/test_library_content.py
@@ -3,10 +3,12 @@
 
 Higher-level tests are in `cms/djangoapps/contentstore/tests/test_libraries.py`.
 """
+from functools import partial
 from unittest.mock import Mock, patch
 
 from bson.objectid import ObjectId
 from fs.memoryfs import MemoryFS
+from lms.djangoapps.courseware.services import ModuleService
 from lxml import etree
 from search.search_engine_base import SearchEngine
 from web_fragments.fragment import Fragment
@@ -61,12 +63,12 @@ def _bind_course_module(self, module):
         def get_module(descriptor):
             """Mocks module_system get_module function"""
             sub_module_system = get_test_system(course_id=module.location.course_key)
-            sub_module_system.get_module = get_module
+            sub_module_system._services['module'] = ModuleService(partial(get_module))
             sub_module_system.descriptor_runtime = descriptor._runtime  # pylint: disable=protected-access
             descriptor.bind_for_student(sub_module_system, self.user_id)
             return descriptor
 
-        module_system.get_module = get_module
+        module_system._services['module'] = ModuleService(partial(get_module))
         module.xmodule_runtime = module_system
 
 
diff --git a/common/lib/xmodule/xmodule/unit_block.py b/common/lib/xmodule/xmodule/unit_block.py
index 2d3dacb65b8b..09d7cf69bdbe 100644
--- a/common/lib/xmodule/xmodule/unit_block.py
+++ b/common/lib/xmodule/xmodule/unit_block.py
@@ -44,7 +44,13 @@ class UnitBlock(XBlock):
     def student_view(self, context=None):
         """Provide default student view."""
         result = Fragment()
-        child_frags = self.runtime.render_children(self, context=context)
+
+        # TODO: uncomment this line and remove _render_children() once
+        # merger of ModuleSystem and DescriptorSystem is complete
+
+        # child_frags = self.runtime.render_children(self, context=context)
+        child_frags = self._render_children(context)
+
         result.add_resources(child_frags)
         result.add_content('<div class="unit-xblock vertical">')
         for frag in child_frags:
@@ -52,6 +58,26 @@ def student_view(self, context=None):
         result.add_content('</div>')
         return result
 
+    def _render_children(self, context):
+        """
+        Use CombinedSystem runtime to get block and render each child individually.
+
+        The runtime.render_children() method was earlier used to render each child
+        However, this caused a problem, when we removed the get_block() and
+        descriptor_runtime properties from the ModuleSystem, as the render_children
+        method ran in the context of LmsModuleSystem which is a child class of
+        ModuleSystem.
+
+        This is intended to be a temporary method until deprecation of all properties
+        of ModuleSystem and merger of ModuleSystem and DescriptorSystem is complete.
+        """
+        results = []
+        for child_id in self.children:
+            child = self.runtime.get_block(child_id)
+            result = self.runtime.render_child(child, context=context)
+            results.append(result)
+        return results
+
     public_view = student_view
 
     def index_dictionary(self):
diff --git a/common/lib/xmodule/xmodule/x_module.py b/common/lib/xmodule/xmodule/x_module.py
index 307d7c815557..678746d2c30b 100644
--- a/common/lib/xmodule/xmodule/x_module.py
+++ b/common/lib/xmodule/xmodule/x_module.py
@@ -1609,6 +1609,21 @@ def filestore(self):
         )
         return self.resources_fs
 
+    @property
+    def get_module(self):
+        """
+        Returns a function to bind module system and user data to given descriptor
+
+        Deprecated in favor of module service.
+        """
+        warnings.warn(
+            'runtime.get_module is deprecated. Please use the module service instead.',
+            DeprecationWarning, stacklevel=3,
+        )
+        module_service = self._services.get('module')
+        if module_service:
+            return partial(module_service.get_module)
+
 
 class ModuleSystem(MetricsMixin, ConfigurableFragmentWrapper, ModuleSystemShim, Runtime):
     """
@@ -1624,8 +1639,8 @@ class ModuleSystem(MetricsMixin, ConfigurableFragmentWrapper, ModuleSystemShim,
     """
 
     def __init__(
-            self, static_url, track_function, get_module,
-            descriptor_runtime, debug=False, hostname="", publish=None,
+            self, static_url, track_function,
+            debug=False, hostname="", publish=None,
             node_path="", course_id=None, error_descriptor_class=None,
             field_data=None, rebind_noauth_module_to_user=None,
             **kwargs):
@@ -1639,12 +1654,6 @@ def __init__(
                          TODO: Not used, and has inconsistent args in different
                          files.  Update or remove.
 
-        get_module - function that takes a descriptor and returns a corresponding
-                         module instance object.  If the current user does not have
-                         access to that location, returns None.
-
-        descriptor_runtime - A `DescriptorSystem` to use for loading xblocks by id
-
         course_id - the course_id containing this module
 
         publish(event) - A function that allows XModules to publish events (such as grade changes)
@@ -1659,13 +1668,10 @@ def __init__(
 
         # Usage_store is unused, and field_data is often supplanted with an
         # explicit field_data during construct_xblock.
-        kwargs.setdefault('id_reader', getattr(descriptor_runtime, 'id_reader', OpaqueKeyReader()))
-        kwargs.setdefault('id_generator', getattr(descriptor_runtime, 'id_generator', AsideKeyGenerator()))
         super().__init__(field_data=field_data, **kwargs)
 
         self.STATIC_URL = static_url
         self.track_function = track_function
-        self.get_module = get_module
         self.DEBUG = self.debug = debug
         self.HOSTNAME = self.hostname = hostname
         self.node_path = node_path
@@ -1676,7 +1682,6 @@ def __init__(
         self.error_descriptor_class = error_descriptor_class
         self.xmodule_instance = None
 
-        self.descriptor_runtime = descriptor_runtime
         self.rebind_noauth_module_to_user = rebind_noauth_module_to_user
 
     def get(self, attr):
@@ -1703,9 +1708,6 @@ def ajax_url(self):
         assert self.xmodule_instance is not None
         return self.handler_url(self.xmodule_instance, 'xmodule_handler', '', '').rstrip('/?')
 
-    def get_block(self, block_id, for_parent=None):  # lint-amnesty, pylint: disable=arguments-differ
-        return self.get_module(self.descriptor_runtime.get_block(block_id, for_parent=for_parent))
-
     def resource_url(self, resource):
         raise NotImplementedError("edX Platform doesn't currently implement XBlock resource urls")
 
@@ -1804,6 +1806,24 @@ def service(self, block, service_name):
 
         return service
 
+    def get_block(self, *args, **kwargs):  # lint-amnesty, pylint: disable=arguments-differ
+        """
+        Get the block using the provided arguments (usually block_id and for_parent).
+
+        The method fetches the block from the DescriptorSystem using the given arguments.
+        If the ModuleSystem is initalized and contains the 'module' service, then the
+        user data and module system is bound to the block.
+        """
+        block_descriptor = self._descriptor_system.get_block(*args, **kwargs)
+
+        if (self._module_system and
+                hasattr(self._module_system, '_services') and
+                self._module_system._services.get('module')):
+            module_service = self._module_system._services.get('module')  # pylint: disable=protected-access
+            return module_service.get_module(block_descriptor)
+
+        return block_descriptor
+
     def __getattr__(self, name):
         """
         If the ModuleSystem doesn't have an attribute, try returning the same attribute from the
diff --git a/lms/djangoapps/courseware/module_render.py b/lms/djangoapps/courseware/module_render.py
index 62157ec648bf..c7705d075937 100644
--- a/lms/djangoapps/courseware/module_render.py
+++ b/lms/djangoapps/courseware/module_render.py
@@ -48,6 +48,7 @@
 from common.djangoapps.static_replace.services import ReplaceURLService
 from common.djangoapps.static_replace.wrapper import replace_urls_wrapper
 from common.djangoapps.xblock_django.constants import ATTR_KEY_USER_ID
+from common.lib.xmodule.xmodule.x_module import AsideKeyGenerator, OpaqueKeyReader
 from capa.xqueue_interface import XQueueService  # lint-amnesty, pylint: disable=wrong-import-order
 from lms.djangoapps.courseware.access import get_user_role, has_access
 from lms.djangoapps.courseware.entrance_exams import user_can_skip_entrance_exam, user_has_passed_entrance_exam
@@ -59,7 +60,7 @@
 )
 from lms.djangoapps.courseware.model_data import DjangoKeyValueStore, FieldDataCache
 from lms.djangoapps.courseware.field_overrides import OverrideFieldData
-from lms.djangoapps.courseware.services import UserStateService
+from lms.djangoapps.courseware.services import ModuleService, UserStateService
 from lms.djangoapps.grades.api import GradesUtilService
 from lms.djangoapps.grades.api import signals as grades_signals
 from lms.djangoapps.lms_xblock.field_data import LmsFieldData
@@ -469,30 +470,6 @@ def make_xqueue_callback(dispatch='score_update'):
         waittime=settings.XQUEUE_WAITTIME_BETWEEN_REQUESTS,
     )
 
-    def inner_get_module(descriptor):
-        """
-        Delegate to get_module_for_descriptor_internal() with all values except `descriptor` set.
-
-        Because it does an access check, it may return None.
-        """
-        # TODO: fix this so that make_xqueue_callback uses the descriptor passed into
-        # inner_get_module, not the parent's callback.  Add it as an argument....
-        return get_module_for_descriptor_internal(
-            user=user,
-            descriptor=descriptor,
-            student_data=student_data,
-            course_id=course_id,
-            track_function=track_function,
-            position=position,
-            wrap_xmodule_display=wrap_xmodule_display,
-            grade_bucket_type=grade_bucket_type,
-            static_asset_path=static_asset_path,
-            user_location=user_location,
-            request_token=request_token,
-            course=course,
-            will_recheck_access=will_recheck_access,
-        )
-
     def get_event_handler(event_type):
         """
         Return an appropriate function to handle the event.
@@ -724,10 +701,25 @@ def rebind_noauth_module_to_user(module, real_user):
     field_data = DateLookupFieldData(descriptor._field_data, course_id, user)  # pylint: disable=protected-access
     field_data = LmsFieldData(field_data, student_data)
 
+    module_service = ModuleService(partial(
+        get_module_for_descriptor_internal,
+        user=user,
+        student_data=student_data,
+        course_id=course_id,
+        track_function=track_function,
+        position=position,
+        wrap_xmodule_display=wrap_xmodule_display,
+        grade_bucket_type=grade_bucket_type,
+        static_asset_path=static_asset_path,
+        user_location=user_location,
+        request_token=request_token,
+        course=course,
+        will_recheck_access=will_recheck_access,
+    ))
+
     system = LmsModuleSystem(
         track_function=track_function,
         static_url=settings.STATIC_URL,
-        get_module=inner_get_module,
         user=user,
         debug=settings.DEBUG,
         hostname=settings.SITE_NAME,
@@ -754,11 +746,13 @@ def rebind_noauth_module_to_user(module, real_user):
             'cache': CacheService(cache),
             'sandbox': SandboxService(contentstore=contentstore, course_id=course_id),
             'xqueue': xqueue_service,
-            'replace_urls': replace_url_service
+            'replace_urls': replace_url_service,
+            'module': module_service
         },
-        descriptor_runtime=descriptor._runtime,  # pylint: disable=protected-access
         rebind_noauth_module_to_user=rebind_noauth_module_to_user,
         request_token=request_token,
+        id_reader=getattr(descriptor._runtime, 'id_reader', OpaqueKeyReader()),  # pylint: disable=protected-access
+        id_generator=getattr(descriptor._runtime, 'id_generator', AsideKeyGenerator()),  # pylint: disable=protected-access
     )
 
     # pass position specified in URL to module through ModuleSystem
diff --git a/lms/djangoapps/courseware/services.py b/lms/djangoapps/courseware/services.py
index 3fa31a3e00fc..8895d2827fdc 100644
--- a/lms/djangoapps/courseware/services.py
+++ b/lms/djangoapps/courseware/services.py
@@ -39,3 +39,18 @@ def get_state_as_dict(self, username_or_email, block_id):
             return json.loads(student_module.state)
         except StudentModule.DoesNotExist:
             return {}
+
+
+class ModuleService:
+    """
+    A service to bind user data and module system to descriptor using the given callback functiion
+    """
+
+    def __init__(self, module_callback) -> None:
+        self.module_callback = module_callback
+
+    def get_module(self, descriptor):
+        """
+        Invokes the callback function to bind user data and module system to given descriptor
+        """
+        return self.module_callback(descriptor=descriptor)
diff --git a/lms/djangoapps/courseware/tests/test_module_render.py b/lms/djangoapps/courseware/tests/test_module_render.py
index d9d8aeae0ef9..14272d14ccdb 100644
--- a/lms/djangoapps/courseware/tests/test_module_render.py
+++ b/lms/djangoapps/courseware/tests/test_module_render.py
@@ -2717,3 +2717,25 @@ def test_replace_jump_to_id_urls(self):
         jump_to_id_base_url = reverse('jump_to_id', kwargs={'course_id': str(self.runtime.course_id), 'module_id': ''})
         assert self.runtime.replace_jump_to_id_urls(html) == \
             static_replace.replace_jump_to_id_urls(html, self.runtime.course_id, jump_to_id_base_url)
+
+    def test_get_module(self):
+        runtime, _ = render.get_module_system_for_user(
+            self.user,
+            self.student_data,
+            self.descriptor,
+            self.course.id,
+            self.track_function,
+            self.request_token,
+            course=self.course,
+        )
+        module = render.get_module_for_descriptor_internal(
+            user=self.user,
+            descriptor=self.descriptor,
+            student_data=self.student_data,
+            course_id=self.course.id,
+            track_function=self.track_function,
+            request_token=self.request_token,
+            course=self.course
+        )
+
+        assert runtime.get_module(self.descriptor) == module
diff --git a/lms/djangoapps/courseware/tests/test_services.py b/lms/djangoapps/courseware/tests/test_services.py
index 1e68317d06b5..3ccd7239c470 100644
--- a/lms/djangoapps/courseware/tests/test_services.py
+++ b/lms/djangoapps/courseware/tests/test_services.py
@@ -3,16 +3,20 @@
 """
 
 
+from functools import partial
 import itertools
 import json
+from unittest.mock import Mock
 
 import ddt
 
+from xmodule.contentstore.django import contentstore
+from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase, SharedModuleStoreTestCase
+from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory
 from common.djangoapps.student.tests.factories import UserFactory
-from lms.djangoapps.courseware.services import UserStateService
+from lms.djangoapps.courseware.module_render import get_module_for_descriptor_internal
+from lms.djangoapps.courseware.services import ModuleService, UserStateService
 from lms.djangoapps.courseware.tests.factories import StudentModuleFactory
-from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase  # lint-amnesty, pylint: disable=wrong-import-order
-from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory  # lint-amnesty, pylint: disable=wrong-import-order
 
 
 @ddt.ddt
@@ -124,3 +128,55 @@ def test_nonexistent_student_module_state(self, state_params, should_use_email):
         self._create_student_module({'key_1': 'value_1'})
         state = UserStateService().get_state_as_dict(**params)
         assert not state
+
+
+class TestModuleService(SharedModuleStoreTestCase):
+    """
+    Tests the Module Service.
+    """
+    COURSE_ID = 'edX/LmsModuleShimTest/2021_Fall'
+
+    @classmethod
+    def setUpClass(cls):
+        """
+        Set up the course and descriptor used to instantiate the runtime.
+        """
+        super().setUpClass()
+        org, number, run = cls.COURSE_ID.split('/')
+        cls.course = CourseFactory.create(org=org, number=number, run=run)
+        cls.descriptor = ItemFactory(category="vertical", parent=cls.course)
+
+    def setUp(self):
+        """
+        Set up the user and other fields that will be used to instantiate the runtime.
+        """
+        super().setUp()
+        self.user = UserFactory(id=232)
+        self.student_data = Mock()
+        self.track_function = Mock()
+        self.request_token = Mock()
+        self.contentstore = contentstore()
+        self.module = get_module_for_descriptor_internal(
+            user=self.user,
+            descriptor=self.descriptor,
+            student_data=self.student_data,
+            course_id=self.course.id,
+            track_function=self.track_function,
+            request_token=self.request_token,
+            course=self.course
+        )
+
+    def test_get_module(self):
+        """
+        Test the get_module method of ModuleService
+        """
+        module_service = ModuleService(partial(
+            get_module_for_descriptor_internal,
+            user=self.user,
+            student_data=self.student_data,
+            course_id=self.course.id,
+            track_function=self.track_function,
+            request_token=self.request_token,
+            course=self.course
+        ))
+        assert module_service.get_module(self.descriptor) == self.module
diff --git a/lms/djangoapps/courseware/tests/test_views.py b/lms/djangoapps/courseware/tests/test_views.py
index 0db2441ef0ac..925d52236124 100644
--- a/lms/djangoapps/courseware/tests/test_views.py
+++ b/lms/djangoapps/courseware/tests/test_views.py
@@ -2446,7 +2446,13 @@ def student_view(self, context):  # pylint: disable=unused-argument
         """
         msg = f"{self.state} != {self.scope_ids.usage_id}"
         assert self.state == str(self.scope_ids.usage_id), msg
-        fragments = self.runtime.render_children(self)
+
+        # TODO: uncomment this line and remove _render_children() once
+        # merger of ModuleSystem and DescriptorSystem is complete
+
+        # fragments = self.runtime.render_children(self)
+        fragments = self._render_children()
+
         result = Fragment(
             content="<p>ViewCheckerPassed: {}</p>\n{}".format(
                 str(self.scope_ids.usage_id),
@@ -2455,6 +2461,26 @@ def student_view(self, context):  # pylint: disable=unused-argument
         )
         return result
 
+    def _render_children(self):
+        """
+        Use CombinedSystem runtime to get block and render each child individually.
+
+        The runtime.render_children() method was earlier used to render each child
+        However, this caused a problem, when we removed the get_block() and
+        descriptor_runtime properties from the ModuleSystem, as the render_children
+        method ran in the context of LmsModuleSystem which is a child class of
+        ModuleSystem.
+
+        This is intended to be a temporary method until deprecation of all properties
+        of ModuleSystem and merger of ModuleSystem and DescriptorSystem is complete.
+        """
+        results = []
+        for child_id in self.children:
+            child = self.runtime.get_block(child_id)
+            result = self.runtime.render_child(child)
+            results.append(result)
+        return results
+
 
 @ddt.ddt
 @set_preview_mode(True)
diff --git a/lms/djangoapps/lms_xblock/test/test_runtime.py b/lms/djangoapps/lms_xblock/test/test_runtime.py
index d85c9e5816ed..66917cdf9df9 100644
--- a/lms/djangoapps/lms_xblock/test/test_runtime.py
+++ b/lms/djangoapps/lms_xblock/test/test_runtime.py
@@ -18,6 +18,7 @@
 from common.djangoapps.student.tests.factories import UserFactory
 from lms.djangoapps.badges.tests.factories import BadgeClassFactory
 from lms.djangoapps.badges.tests.test_models import get_image
+from lms.djangoapps.courseware.services import ModuleService
 from lms.djangoapps.lms_xblock.runtime import LmsModuleSystem
 from xmodule.modulestore.django import ModuleI18nService  # lint-amnesty, pylint: disable=wrong-import-order
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase  # lint-amnesty, pylint: disable=wrong-import-order
@@ -62,10 +63,13 @@ def setUp(self):
         self.runtime = LmsModuleSystem(
             static_url='/static',
             track_function=Mock(),
-            get_module=Mock(),
+            services={
+                'module': ModuleService(Mock())
+            },
             course_id=self.course_key,
             user=Mock(),
-            descriptor_runtime=Mock(),
+            id_reader=Mock(),
+            id_generator=Mock()
         )
 
     def test_trailing_characters(self):
@@ -127,10 +131,13 @@ def setUp(self):
         self.runtime = LmsModuleSystem(
             static_url='/static',
             track_function=Mock(),
-            get_module=Mock(),
+            services={
+                'module': ModuleService(Mock())
+            },
             user=self.user,
             course_id=self.course_id,
-            descriptor_runtime=Mock(),
+            id_reader=Mock(),
+            id_generator=Mock()
         )
         self.scope = 'course'
         self.key = 'key1'
@@ -177,10 +184,13 @@ def create_runtime(self):
         return LmsModuleSystem(
             static_url='/static',
             track_function=Mock(),
-            get_module=Mock(),
+            services={
+                'module': ModuleService(Mock())
+            },
             course_id=self.course_id,
             user=self.user,
-            descriptor_runtime=Mock(),
+            id_reader=Mock(),
+            id_generator=Mock()
         )
 
     @patch.dict(settings.FEATURES, {'ENABLE_OPENBADGES': True})
@@ -230,10 +240,13 @@ def setUp(self):
         self.runtime = LmsModuleSystem(
             static_url='/static',
             track_function=Mock(),
-            get_module=Mock(),
+            services={
+                'module': ModuleService(Mock())
+            },
             course_id=self.course.id,
             user=Mock(),
-            descriptor_runtime=Mock(),
+            id_reader=Mock(),
+            id_generator=Mock()
         )
 
         self.mock_block = Mock()
diff --git a/openedx/tests/completion_integration/test_services.py b/openedx/tests/completion_integration/test_services.py
index 0529ec7b7188..2752b53ef576 100644
--- a/openedx/tests/completion_integration/test_services.py
+++ b/openedx/tests/completion_integration/test_services.py
@@ -3,6 +3,7 @@
 """
 
 
+from functools import partial
 import ddt
 from completion.models import BlockCompletion
 from completion.services import CompletionService
@@ -15,6 +16,7 @@
 from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory, LibraryFactory
 from xmodule.tests import get_test_system
 
+from lms.djangoapps.courseware.services import ModuleService
 from openedx.core.djangolib.testing.utils import skip_unless_lms
 from common.djangoapps.student.tests.factories import UserFactory
 
@@ -128,12 +130,12 @@ def _bind_course_module(self, module):
         def get_module(descriptor):
             """Mocks module_system get_module function"""
             sub_module_system = get_test_system(course_id=module.location.course_key)
-            sub_module_system.get_module = get_module
+            sub_module_system._services['module'] = ModuleService(partial(get_module))  # pylint: disable=protected-access
             sub_module_system.descriptor_runtime = descriptor._runtime  # pylint: disable=protected-access
             descriptor.bind_for_student(sub_module_system, self.user.id)
             return descriptor
 
-        module_system.get_module = get_module
+        module_system._services['module'] = ModuleService(partial(get_module))  # pylint: disable=protected-access
         module.xmodule_runtime = module_system
 
     def test_completion_service(self):