diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9d2f4423..48ba9a56 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,9 +8,9 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ["3.7", "3.8"]
-        django-version: ["2.1.1", "3.1.4"]
-        database-engine: ["postgres", "mysql"]
+        python-version: [ "3.7", "3.8" ]
+        django-version: [ "2.1.1", "3.1.4" ]
+        database-engine: [ "postgres", "mysql", "mssql"]
 
     services:
       postgres:
@@ -37,6 +37,15 @@ jobs:
         ports:
           - 3306:3306
 
+
+      mssqldb:
+        image: "mcr.microsoft.com/mssql/server:2017-latest"
+        env:
+          ACCEPT_EULA: y
+          SA_PASSWORD: '~Test123'
+        ports:
+          - 1433:1433
+
     steps:
       - name: Checkout code
         uses: actions/checkout@v2
@@ -73,11 +82,16 @@ jobs:
           mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql --protocol=TCP -h localhost -u root -prootpassword mysql
         if: matrix.database-engine == 'mysql'
 
+      - name: Prepare mssql database
+        run: |
+         /opt/mssql-tools/bin/sqlcmd -S localhost -U sa -P '~Test123' -m-1 -Q 'CREATE DATABASE [binder-test];'
+        if: matrix.database-engine == 'mssql'
+
       - name: Run tests
         run: |
           .venv/bin/coverage run --include="binder/*" setup.py test
         env:
-          BINDER_TEST_MYSQL: ${{ matrix.database-engine == 'mysql' && 1 || 0 }}
+          BINDER_TEST_DATABASE_ENGINE: ${{ matrix.database-engine }}
           CY_RUNNING_INSIDE_CI: 1
 
       - name: Upload coverage report
diff --git a/README.md b/README.md
index da9d2020..7c5527da 100644
--- a/README.md
+++ b/README.md
@@ -14,11 +14,19 @@ There are two ways to run the tests:
 - Run with docker `docker-compose run binder ./setup.py test`
   - Access the test database directly by with `docker-compose run db psql -h db -U postgres`.
   - It may be possible to recreate the test database (for example when you added/changed models). One way of achieving this is to just remove all the docker images that were build `docker-compose rm`. The database will be created during the setup in `tests/__init__.py`.
-
+   
 The tests are set up in such a way that there is no need to keep migration files. The setup procedure in `tests/__init__.py` handles the preparation of the database by directly calling some build-in Django commands.
 
 To only run a selection of the tests, use the `-s` flag like `./setup.py test -s tests.test_some_specific_test`.
 
+### Running test other database systems
+Locally the tests can be run for MySQL or MSSQL by overriding the `BINDER_TEST_DATABASE_ENGINE` environment variable:
+
+- `docker-compose run -e BINDER_TEST_DATABASE_ENGINE=mysql binder ./setup.py test` for MySQL
+- `docker-compose run -e BINDER_TEST_DATABASE_ENGINE=mssql binder ./setup.py test` for MsSQL
+
+
+
 ## MySQL support
 
 MySQL is supported, but only with the goal to replace it with
diff --git a/binder/models.py b/binder/models.py
index 3764054b..7c526754 100644
--- a/binder/models.py
+++ b/binder/models.py
@@ -405,6 +405,7 @@ class Meta:
 
 	def save(self, *args, **kwargs):
 		self.full_clean() # Never allow saving invalid models!
+
 		return super().save(*args, **kwargs)
 
 
diff --git a/binder/views.py b/binder/views.py
index c12c1760..56e3446c 100644
--- a/binder/views.py
+++ b/binder/views.py
@@ -315,11 +315,18 @@ class ModelView(View):
 	#  }
 	virtual_relations = {}
 
+	@property
+	def database_type(self):
+		return {
+			'mysql': 'mysql',
+			'microsoft': 'mssql',
+		}.get(connections[self.model.objects.db].vendor, 'postgres')
+
 	@property
 	def AggStrategy(self):
-		if connections[self.model.objects.db].vendor == 'mysql':
+		if self.database_type == 'mysql':
 			return GroupConcat
-		if connections[self.model.objects.db].vendor == 'microsoft':
+		if self.database_type == 'mssql':
 			return StringAgg
 		return OrderableArrayAgg
 
@@ -869,6 +876,14 @@ def _follow_related(self, fieldspec):
 	# permission scoping.  This will be done when fetching the actual
 	# objects.
 	def _get_with_ids(self, pks, request, include_annotations, with_map, where_map):
+		if self.database_type == 'mssql':
+			with_ids = {}
+			for key, sub_with_map in with_map.items():
+				with_ids.update(self._base_get_with_ids(pks, request, include_annotations, {key: sub_with_map}, where_map))
+			return with_ids
+		return self._base_get_with_ids( pks, request, include_annotations, with_map, where_map)
+
+	def _base_get_with_ids(self, pks, request, include_annotations, with_map, where_map):
 		result = {}
 
 		annotations = {}
diff --git a/docker-compose.yml b/docker-compose.yml
index 5e890a8a..dcdacd3d 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -4,9 +4,28 @@ services:
   db:
     image: postgres:11.5
   binder:
-    build: .
+    build:
+      context: ./
+      dockerfile: docker/binder/Dockerfile
     command: tail -f /dev/null
     volumes:
       - .:/binder
     depends_on:
       - db
+      - mysql
+      - mssqldb
+  mysql:
+    image: mysql
+    environment:
+      MYSQL_ROOT_PASSWORD: rootpassword
+    ports:
+      - 3306:3306
+  mssqldb:
+    build:
+      context: ./
+      dockerfile: docker/mssqldb/Dockerfile
+    environment:
+      ACCEPT_EULA: y
+      SA_PASSWORD: '~Test123'
+    ports:
+      - 1433:1433
\ No newline at end of file
diff --git a/Dockerfile b/docker/binder/Dockerfile
similarity index 58%
rename from Dockerfile
rename to docker/binder/Dockerfile
index 41f16d7d..bc1c2d94 100644
--- a/Dockerfile
+++ b/docker/binder/Dockerfile
@@ -1,5 +1,6 @@
-FROM python:3
+FROM python:3-buster
 ENV PYTHONUNBUFFERED 1
 RUN mkdir /binder
 WORKDIR /binder
 ADD . /binder
+RUN ./install-mssql-driver.sh
diff --git a/docker/mssqldb/Dockerfile b/docker/mssqldb/Dockerfile
new file mode 100644
index 00000000..2e1ed3ab
--- /dev/null
+++ b/docker/mssqldb/Dockerfile
@@ -0,0 +1,12 @@
+FROM mcr.microsoft.com/mssql/server:2017-latest
+WORKDIR /
+
+ENV ACCEPT_EULA Y
+ENV SA_PASSWORD "~Test123"
+
+COPY docker/mssqldb/init /init
+COPY docker/mssqldb/bootstrap.sql /bootstrap.sql
+COPY docker/mssqldb/entrypoint.sh /entrypoint.sh
+
+EXPOSE 1433
+CMD /entrypoint.sh
\ No newline at end of file
diff --git a/docker/mssqldb/bootstrap.sql b/docker/mssqldb/bootstrap.sql
new file mode 100644
index 00000000..9b64f644
--- /dev/null
+++ b/docker/mssqldb/bootstrap.sql
@@ -0,0 +1,4 @@
+USE [master]
+GO
+CREATE DATABASE [binder-test]
+GO
\ No newline at end of file
diff --git a/docker/mssqldb/entrypoint.sh b/docker/mssqldb/entrypoint.sh
new file mode 100755
index 00000000..962beb49
--- /dev/null
+++ b/docker/mssqldb/entrypoint.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+#start SQL Server, start the script to create the DB and import the data, start the app
+nohup /init &
+/opt/mssql/bin/sqlservr
diff --git a/docker/mssqldb/init b/docker/mssqldb/init
new file mode 100755
index 00000000..1f63253b
--- /dev/null
+++ b/docker/mssqldb/init
@@ -0,0 +1,7 @@
+#!/bin/sh
+
+#wait for the SQL Server to come up
+sleep 20s
+
+echo "Running CREATE DATABASE"
+/opt/mssql-tools/bin/sqlcmd -S localhost -U sa -P '~Test123' -m-1 -i bootstrap.sql
\ No newline at end of file
diff --git a/install-mssql-driver.sh b/install-mssql-driver.sh
new file mode 100755
index 00000000..05888a87
--- /dev/null
+++ b/install-mssql-driver.sh
@@ -0,0 +1,14 @@
+curl https://packages.microsoft.com/keys/microsoft.asc | apt-key add -
+
+#Download appropriate package for the OS version
+#Choose only ONE of the following, corresponding to your OS version
+
+#Debian 10
+curl https://packages.microsoft.com/config/debian/10/prod.list > /etc/apt/sources.list.d/mssql-release.list
+
+apt-get update
+ACCEPT_EULA=Y apt-get install -y msodbcsql17
+# optional: for bcp and sqlcmd
+ACCEPT_EULA=Y apt-get install -y mssql-tools
+echo 'export PATH="$PATH:/opt/mssql-tools/bin"' >> ~/.bashrc
+apt-get install -y unixodbc-dev
\ No newline at end of file
diff --git a/project/packages.pip b/project/packages.pip
index 88f0be8c..c49e8afd 100644
--- a/project/packages.pip
+++ b/project/packages.pip
@@ -3,4 +3,6 @@ Pillow
 django-request-id
 psycopg2
 requests
-openpyxl
\ No newline at end of file
+openpyxl
+django-pyodbc-azure
+django-pyodbc
\ No newline at end of file
diff --git a/setup.py b/setup.py
index 31a0f90f..99184980 100755
--- a/setup.py
+++ b/setup.py
@@ -9,6 +9,14 @@
 # allow setup.py to be run from any path
 os.chdir(os.path.normpath(os.path.join(os.path.abspath(__file__), os.pardir)))
 
+test_require_database_engine = {
+	'mysql': ['mysqlclient >= 1.3.12', 'psycopg2 >= 2.7'],
+	'mssql': ['django-pyodbc-azure >= 2.1.0.0', 'django-pyodbc >= 1.1.3', 'django-hijack == 2.1.10', 'psycopg2 >= 2.7'],
+	# Alternative mssql setup with django 3 setup. For later
+	# 'mssql': ['mssql-django==1.0rc1', 'psycopg2 >= 2.7']
+}.get(os.environ.get('BINDER_TEST_DATABASE_ENGINE'),  ['psycopg2 >= 2.7'])
+
+
 setup(
 	name='django-binder',
 	version='1.5.0',
@@ -44,11 +52,7 @@
 	],
 	tests_require=[
 		'django-hijack >= 2.1.10',
-		(
-			'mysqlclient >= 1.3.12'
-			if os.environ.get('BINDER_TEST_MYSQL', '0') == '1' else
-			'psycopg2 >= 2.7'
-		),
+		*test_require_database_engine,
 		"openpyxl >= 3.0.0"
 	],
 )
diff --git a/tests/__init__.py b/tests/__init__.py
index 4dcaf8bd..bea87d5d 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -3,18 +3,12 @@
 from django.core.management import call_command
 import os
 
-if (
-	os.path.exists('/.dockerenv') and
-	'CY_RUNNING_INSIDE_CI' not in os.environ
-):
-	db_settings = {
-		'ENGINE': 'django.db.backends.postgresql',
-		'NAME': 'postgres',
-		'USER': 'postgres',
-		'HOST': 'db',
-		'PORT': 5432,
-	}
-elif os.environ.get('BINDER_TEST_MYSQL', '0') == '1':
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') == 'mssql':
+	os.system("/opt/mssql-tools/bin/sqlcmd -S localhost -U sa -P '~Test123' -m-1 -Q 'CREATE DATABASE [binder-test];'")
+
+
+
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') == 'mysql':
 	db_settings = {
 		'ENGINE': 'django.db.backends.mysql',
 		'NAME': 'binder-test',
@@ -23,6 +17,26 @@
 		'USER': 'root',
 		'PASSWORD': 'rootpassword',
 	}
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') == 'mssql':
+	db_settings = {
+		'ENGINE': 'sql_server.pyodbc',
+		'NAME': 'binder-test',
+		'TIME_ZONE': 'UTC',
+		'HOST': 'mssqldb',
+		'USER': 'sa',
+		'PASSWORD': '~Test123',
+		'OPTIONS': {
+			'driver': 'ODBC Driver 17 for SQL Server',
+		},
+	}
+elif (os.path.exists('/.dockerenv') and  'CY_RUNNING_INSIDE_CI' not in os.environ):
+    db_settings = {
+        'ENGINE': 'django.db.backends.postgresql',
+        'NAME': 'postgres',
+        'USER': 'postgres',
+        'HOST': 'db',
+        'PORT': 5432,
+    }
 else:
 	db_settings = {
 		'ENGINE': 'django.db.backends.postgresql_psycopg2',
@@ -31,6 +45,7 @@
 		'USER': 'postgres',
 	}
 
+
 settings.configure(**{
 	'DEBUG': True,
 	'SECRET_KEY': 'testy mctestface',
@@ -74,6 +89,12 @@
 				'level': 'DEBUG',
 				'class': 'logging.StreamHandler',
 			},
+            'file': {
+                'level': 'DEBUG',
+                'class': 'logging.handlers.WatchedFileHandler',
+                'filename': 'backend.log',
+                'filters': [],
+            },
 		},
 		'loggers': {
 			# We override only this one to avoid logspam
@@ -83,7 +104,13 @@
 				'handlers': ['console'],
 				'level': 'ERROR',
 			},
-		}
+            # 'django.db.backends': {
+            #     'handlers': ['console', 'file'],
+            #     'level': 'DEBUG',
+            #     'propagate': True,
+            # },
+        }
+
 	},
 	'BINDER_PERMISSION': {
 		'default': [
@@ -110,7 +137,6 @@
 		'admin': []
 	}
 })
-
 setup()
 
 # Do the dance to ensure the models are synched to the DB.
diff --git a/tests/filters/test_time_filters.py b/tests/filters/test_time_filters.py
index 76b923ef..b1e702e4 100644
--- a/tests/filters/test_time_filters.py
+++ b/tests/filters/test_time_filters.py
@@ -6,7 +6,7 @@
 import os
 
 # This is not possible in
-if os.environ.get('BINDER_TEST_MYSQL', '0') != '1':
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') not in ['mssql', 'mysql']:
 	class TimeFiltersTest(TestCase):
 
 		def setUp(self):
diff --git a/tests/test_multi_put.py b/tests/test_multi_put.py
index b664443c..dfa4f90f 100644
--- a/tests/test_multi_put.py
+++ b/tests/test_multi_put.py
@@ -176,6 +176,8 @@ def test_put_relations_from_referencing_side(self):
 		}
 		response = self.client.put('/animal/', data=json.dumps(with_model_data), content_type='application/json')
 
+		print(response.content)
+
 		self.assertEqual(response.status_code, 200)
 
 		returned_data = jsonloads(response.content)
diff --git a/tests/test_nulls_last.py b/tests/test_nulls_last.py
index bd459014..e67b81bc 100644
--- a/tests/test_nulls_last.py
+++ b/tests/test_nulls_last.py
@@ -26,7 +26,7 @@ def test_order_by_nulls_last(self):
 		self._load_test_data()
 
 		# MySQL has different defaults when no nulls option is selected...
-		if os.environ.get('BINDER_TEST_MYSQL', '0') != '0':
+		if os.environ.get('BINDER_TEST_DATABASE_ENGINE') in ['mssql', 'mysql']:
 			self._assert_order('last_seen', ['4', '5', '1', '2', '3'])
 			self._assert_order('-last_seen', ['3', '2', '1', '4', '5'])
 		else:
@@ -46,7 +46,7 @@ def test_order_by_nulls_last_on_annotation(self):
 		self._load_test_data()
 
 		# MySQL has different defaults when no nulls option is selected...
-		if os.environ.get('BINDER_TEST_MYSQL', '0') != '0':
+		if os.environ.get('BINDER_TEST_DATABASE_ENGINE') in ['mssql', 'mysql']:
 			self._assert_order('last_present', ['4', '5', '1', '2', '3'])
 			self._assert_order('-last_present', ['3', '2', '1', '4', '5'])
 		else:
diff --git a/tests/test_postgres_fields.py b/tests/test_postgres_fields.py
index 4713d218..b5a9a828 100644
--- a/tests/test_postgres_fields.py
+++ b/tests/test_postgres_fields.py
@@ -7,12 +7,12 @@
 from binder.json import jsonloads
 from django.contrib.auth.models import User
 
-if os.environ.get('BINDER_TEST_MYSQL', '0') == '0':
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') not in ['mysql', 'mssql']:
 	from .testapp.models import FeedingSchedule, Animal, Zoo
 
 # TODO: Currently these only really test filtering.  Move to test/filters?
 @unittest.skipIf(
-	os.environ.get('BINDER_TEST_MYSQL', '0') != '0',
+	os.environ.get('BINDER_TEST_DATABASE_ENGINE') in ['mysql', 'mssql'],
 	"Only available with PostgreSQL"
 )
 class PostgresFieldsTest(TestCase):
diff --git a/tests/testapp/models/__init__.py b/tests/testapp/models/__init__.py
index d83931a2..ae3d5b5d 100644
--- a/tests/testapp/models/__init__.py
+++ b/tests/testapp/models/__init__.py
@@ -7,7 +7,7 @@
 from .contact_person import ContactPerson
 from .costume import Costume
 # This is a Postgres-specific model
-if os.environ.get('BINDER_TEST_MYSQL', '0') != '1':
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') not in ['mysql', 'mssql']:
 	from .feeding_schedule import FeedingSchedule
 from .gate import Gate
 from .nickname import Nickname, NullableNickname
diff --git a/tests/testapp/models/animal.py b/tests/testapp/models/animal.py
index 85d844e0..d2d22f8e 100644
--- a/tests/testapp/models/animal.py
+++ b/tests/testapp/models/animal.py
@@ -11,6 +11,7 @@ class Concat(Func):
 
 # From the api docs: an animal with a name.
 class Animal(LoadedValuesMixin, BinderModel):
+	# id = models.IntegerField(primary_key=True, null=True, blank=True)
 	name = models.TextField(max_length=64)
 	zoo = models.ForeignKey('Zoo', on_delete=models.CASCADE, related_name='animals', blank=True, null=True)
 	zoo_of_birth = models.ForeignKey('Zoo', on_delete=models.CASCADE, related_name='+', blank=True, null=True) # might've been born outside captivity
diff --git a/tests/testapp/models/zoo.py b/tests/testapp/models/zoo.py
index a6b1737c..8d931404 100644
--- a/tests/testapp/models/zoo.py
+++ b/tests/testapp/models/zoo.py
@@ -17,13 +17,14 @@ def delete_files(sender, instance=None, **kwargs):
 # From the api docs: a zoo with a name.  It also has a founding date,
 # which is nullable (representing "unknown").
 class Zoo(BinderModel):
+	# id = models.IntegerField(primary_key=True, null=True, blank=True)
 	name = models.TextField()
 	founding_date = models.DateField(null=True, blank=True)
 	floor_plan = models.ImageField(upload_to='floor-plans', null=True, blank=True)
 	# It is important that this m2m relationship is defined on this model, one of the tests depends on this fact
 	contacts = models.ManyToManyField('ContactPerson', blank=True, related_name='zoos')
 	# We assume that a person can only be the director of one zoo, one of the tests depends on this fact
-	director = models.OneToOneField('ContactPerson', on_delete=models.SET_NULL, blank=True, null=True, related_name='managing_zoo')
+	director = models.ForeignKey('ContactPerson', on_delete=models.SET_NULL, blank=True, null=True, related_name='managing_zoo')
 	most_popular_animals = models.ManyToManyField('Animal', blank=True, related_name='+')
 	opening_time = models.TimeField(default=datetime.time(9, 0, 0))
 
diff --git a/tests/testapp/views/__init__.py b/tests/testapp/views/__init__.py
index 7dd1f4f0..6f4a0531 100644
--- a/tests/testapp/views/__init__.py
+++ b/tests/testapp/views/__init__.py
@@ -10,7 +10,7 @@
 from .country import CountryView
 
 # This has a Postgres-specific model
-if os.environ.get('BINDER_TEST_MYSQL', '0') != '1':
+if os.environ.get('BINDER_TEST_DATABASE_ENGINE') not in ['mysql', 'mssql']:
 	from .feeding_schedule import FeedingScheduleView
 from .gate import GateView
 from .lion import LionView