diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index fb1e4abf..dd9fe866 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -5,7 +5,8 @@ ChangeLog
 master (unreleased)
 ===================
 
-Nothing here yet.
+* Renamed exception class for unknown access (#166)
+* Added str() methods to models (#167)
 
 Release 0.6.0 (2017-01-17)
 ==========================
diff --git a/demo/tests/test_models.py b/demo/tests/test_models.py
new file mode 100644
index 00000000..29cbab97
--- /dev/null
+++ b/demo/tests/test_models.py
@@ -0,0 +1,77 @@
+# -*- coding: utf-8 -*-
+
+from __future__ import unicode_literals
+
+from django.test import TestCase
+
+from formidable import constants
+from formidable.forms import fields, FormidableForm
+
+
+class FormTest(FormidableForm):
+    title = fields.TitleField(label='Jedi Onboarding')
+    helptext = fields.HelpTextField(text='youhou')
+    mytext = fields.CharField(label='Name', accesses={
+        'padawan': constants.EDITABLE,
+        'jedi': constants.REQUIRED,
+        'jedi-master': constants.HIDDEN,
+        'human': constants.EDITABLE,
+    })
+    dropdown = fields.ChoiceField(
+        choices=(('tutu', 'toto'), ('foo', 'bar')),
+        accesses={'jedi': 'EDITABLE'}
+    )
+
+
+class UnicodeTestCase(TestCase):
+
+    def setUp(self):
+        super(UnicodeTestCase, self).setUp()
+        self.formidable = FormTest.to_formidable(label='label')
+
+    def test_formidable(self):
+        self.assertEqual(str(self.formidable), 'label')
+
+    def test_field(self):
+        field = self.formidable.fields.get(slug='title')
+        self.assertEqual(str(field), 'Jedi Onboarding')
+
+    def test_default(self):
+        field = self.formidable.fields.get(slug='title')
+        default = field.defaults.create(value='Value')
+        self.assertEqual(str(default), 'Value')
+
+    def test_item(self):
+        field = self.formidable.fields.get(slug='dropdown')
+        self.assertEqual(field.items.all().count(), 2)
+        tutu, foo = field.items.all()
+        self.assertEqual(str(tutu), 'toto: tutu')
+        self.assertEqual(str(foo), 'bar: foo')
+
+    def test_access(self):
+        field = self.formidable.fields.get(slug='mytext')
+        self.assertEqual(field.accesses.all().count(), 4)
+
+        human, jedi, jedi_master, padawan = field.accesses.all().order_by('access_id')  # noqa
+        self.assertEqual(str(human), 'human: EDITABLE')
+        self.assertEqual(str(jedi), 'jedi: REQUIRED')
+        self.assertEqual(str(jedi_master), 'jedi-master: HIDDEN')
+        self.assertEqual(str(padawan), 'padawan: EDITABLE')
+
+    def test_validation(self):
+        field = self.formidable.fields.get(slug='dropdown')
+        validation = field.validations.create(value='Value', type='Type')
+        self.assertEqual(str(validation), 'Value: Type')
+
+    def test_preset(self):
+        preset = self.formidable.presets.create(slug='slug')
+        self.assertEqual(str(preset), 'slug')
+
+    def test_preset_argument(self):
+        preset = self.formidable.presets.create(slug='slug')
+
+        argument = preset.arguments.create(slug='slug', value='Value')
+        self.assertEqual(str(argument), 'slug: value Value')
+
+        argument.field_id = '12345'
+        self.assertEqual(str(argument), 'slug: field #12345')
diff --git a/formidable/models.py b/formidable/models.py
index 731c157b..14fc335f 100644
--- a/formidable/models.py
+++ b/formidable/models.py
@@ -54,6 +54,9 @@ def from_json(definition_schema, **kwargs):
 
         raise ValidationError(serializer.errors)
 
+    def __str__(self):
+        return '{formidable.label}'.format(formidable=self)
+
 
 class Field(models.Model):
 
@@ -80,12 +83,18 @@ def get_next_order(self):
         agg = self.items.aggregate(models.Max('order'))
         return agg['order__max'] + 1 if agg['order__max'] is not None else 0
 
+    def __str__(self):
+        return '{field.label}'.format(field=self)
+
 
 class Default(models.Model):
 
     value = models.CharField(max_length=256)
     field = models.ForeignKey(Field, related_name='defaults')
 
+    def __str__(self):
+        return '{default.value}'.format(default=self)
+
 
 class Item(models.Model):
     field = models.ForeignKey(Field, related_name='items')
@@ -94,8 +103,8 @@ class Item(models.Model):
     order = models.IntegerField()
     help_text = models.TextField(blank=True, null=True)
 
-    def __unicode__(self):
-        return '{item.key}: {item.value}'.format(item=self)
+    def __str__(self):
+        return '{item.label}: {item.value}'.format(item=self)
 
 
 class Access(models.Model):
@@ -114,6 +123,10 @@ class Meta:
         ('TABLE', 'Table'),
     ))
 
+    def __str__(self):
+        return '{access.access_id}: {access.level}'.format(
+            access=self)
+
 
 class Validation(models.Model):
     field = models.ForeignKey(Field, related_name='validations')
@@ -121,12 +134,19 @@ class Validation(models.Model):
     type = models.CharField(max_length=256)
     message = models.TextField(blank=True, null=True)
 
+    def __str__(self):
+        return '{validation.value}: {validation.type}'.format(
+            validation=self)
+
 
 class Preset(models.Model):
     form = models.ForeignKey(Formidable, related_name='presets')
     slug = models.CharField(max_length=128)
     message = models.TextField(null=True, blank=True)
 
+    def __str__(self):
+        return '{preset.slug}'.format(preset=self)
+
 
 class PresetArg(models.Model):
     preset = models.ForeignKey(Preset, related_name='arguments')
@@ -134,7 +154,7 @@ class PresetArg(models.Model):
     value = models.CharField(max_length=128, null=True, blank=True)
     field_id = models.CharField(max_length=128, null=True, blank=True)
 
-    def __unicode__(self):
+    def __str__(self):
         if self.field_id:
             return '{preset_arg.slug}: field #{preset_arg.field_id}'.format(
                 preset_arg=self)