diff --git a/geeksbot_web/users/serializers.py b/geeksbot_web/users/serializers.py
index 00f6675..120067c 100644
--- a/geeksbot_web/users/serializers.py
+++ b/geeksbot_web/users/serializers.py
@@ -36,6 +36,17 @@ class UserSerializer(serializers.HyperlinkedModelSerializer):
             }
         }
 
+    def update(self, instance, validated_data):
+        if 'username' in validated_data and instance.username != validated_data['username']:
+            prev_usernames = set(instance.previous_usernames)
+            prev_usernames.add(instance.username)
+            validated_data['previous_usernames'] = list(prev_usernames)
+        if 'discriminator' in validated_data and instance.discriminator != validated_data['discriminator']:
+            prev_discrims = set(instance.previous_discriminators)
+            prev_discrims.add(instance.discriminator)
+            validated_data['previous_discriminators'] = list(prev_discrims)
+        super(UserSerializer, self).update(instance, validated_data)
+
 
 class UserLogSerializer(serializers.ModelSerializer):
     class Meta: