diff --git a/atlas/migrations/0010_auto_20211129_2214.py b/atlas/migrations/0010_auto_20211129_2214.py
new file mode 100644
index 00000000..e24526bb
--- /dev/null
+++ b/atlas/migrations/0010_auto_20211129_2214.py
@@ -0,0 +1,33 @@
+# Generated by Django 3.2.8 on 2021-11-29 22:14
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('atlas', '0009_seriesfinding_viewport_json'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='case',
+            name='discussion',
+            field=models.TextField(blank=True, null=True),
+        ),
+        migrations.CreateModel(
+            name='Differential',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('text', models.TextField(blank=True, null=True)),
+                ('case', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='differentialcase', to='atlas.case')),
+                ('condition', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='atlas.condition')),
+            ],
+        ),
+        migrations.AddField(
+            model_name='case',
+            name='differential',
+            field=models.ManyToManyField(related_name='casedifferential', through='atlas.Differential', to='atlas.Condition'),
+        ),
+    ]
diff --git a/atlas/models.py b/atlas/models.py
index 90c6a913..98d33e43 100644
--- a/atlas/models.py
+++ b/atlas/models.py
@@ -113,6 +113,16 @@ class Subspecialty(models.Model):
         return self.name
 
 
+class Differential(models.Model):
+    condition = models.ForeignKey(
+        Condition, on_delete=models.CASCADE
+    )
+    case = models.ForeignKey(
+        "Case", on_delete=models.CASCADE, related_name="differentialcase"
+    )
+    text = models.TextField(null=True, blank=True)
+
+
 @reversion.register
 class Case(models.Model):
     # class SubspecialtyChoices(models.TextChoices):
@@ -137,6 +147,7 @@ class Case(models.Model):
     )
 
     history = models.TextField(null=True, blank=True)
+    discussion = models.TextField(null=True, blank=True)
 
     # findings = models.TextField(null=True, blank=True)
 
@@ -145,6 +156,8 @@ class Case(models.Model):
 
     condition = models.ManyToManyField(Condition, blank=True)
 
+    differential = models.ManyToManyField(Condition, through=Differential, related_name="casedifferential")
+
     sign = tagulous.models.TagField(
         to=Sign, blank=True, help_text="Radiological signs in the question"
     )