diff --git a/proposals/utils/validate_proposal.py b/proposals/utils/validate_proposal.py
index 810cc21f0..90db5dd2a 100644
--- a/proposals/utils/validate_proposal.py
+++ b/proposals/utils/validate_proposal.py
@@ -12,7 +12,7 @@
 from interventions.forms import InterventionForm
 from observations.forms import ObservationForm
 from studies.forms import StudyForm, StudyDesignForm
-from tasks.forms import SessionUpdateForm, SessionEndForm, TaskForm
+from tasks.forms import SessionUpdateForm, SessionEndForm, TaskForm, SessionOverviewForm
 from ..forms import (
     ProposalForm,
     WmoForm,
@@ -157,7 +157,24 @@ def _build_forms(proposal: Proposal) -> OrderedDict:
                     None,
                 )
 
-        if study.has_sessions:
+        if study.has_no_sessions():
+            session_overview_key = "{}_session_overview".format(
+                key_base,
+            )
+            forms[session_overview_key] = (
+                SessionOverviewForm,
+                reverse(
+                    "tasks:session_overview",
+                    args=[
+                        study.pk,
+                    ],
+                ),
+                _("Overzicht van het takenonderzoek (traject {})").format(
+                    study.order,
+                ),
+                study,
+            )
+        elif study.has_sessions:
             for session in study.session_set.all():
                 session_start_key = "{}_session_{}_start".format(
                     key_base,
@@ -247,7 +264,13 @@ def get_form_errors(proposal: Proposal) -> list:
                 kwargs["proposal"] = proposal
 
             if issubclass(
-                form_class, (InterventionForm, ObservationForm, SessionUpdateForm)
+                form_class,
+                (
+                    InterventionForm,
+                    ObservationForm,
+                    SessionUpdateForm,
+                    SessionOverviewForm,
+                ),
             ):
                 kwargs["study"] = obj.study
 
diff --git a/tasks/forms.py b/tasks/forms.py
index 0d3b69fc5..eed1bb07b 100644
--- a/tasks/forms.py
+++ b/tasks/forms.py
@@ -1,10 +1,12 @@
 # -*- encoding: utf-8 -*-
 
 from django import forms
+from django.forms import ModelForm
 from django.utils.translation import ugettext_lazy as _
 
 from main.forms import ConditionalModelForm, SoftValidationMixin
 from main.utils import YES_NO
+from tasks.models import Study
 from .models import Session, Task
 
 
@@ -155,6 +157,10 @@ class Meta:
         model = Session
         fields = ["tasks_duration"]
 
+    _soft_validation_fields = [
+        "tasks_duration",
+    ]
+
     def __init__(self, *args, **kwargs):
         """
         - Set the tasks_duration label
@@ -189,3 +195,29 @@ def clean_tasks_duration(self):
             )
 
         return tasks_duration
+
+
+class SessionOverviewForm(SoftValidationMixin, ModelForm):
+    """This is form is mostly used to make the navigation work on
+    SessionOverview and SessionStart. However, it is also use to validate
+    that if study.has_session, it also contains sessions."""
+
+    class Meta:
+        model = Study
+        fields = []
+
+    def get_soft_validation_fields(self):
+        return self.errors
+
+    def clean(self):
+        cleaned_data = super(SessionOverviewForm, self).clean()
+
+        if self.instance.has_no_sessions():
+            self.add_error(
+                None,
+                _(
+                    "Je hebt aangegeven dat traject {} sessie's en taken bevat, maar er zijn nog geen sessie's aangemaakt."
+                ).format(self.instance.order),
+            )
+
+        return cleaned_data
diff --git a/tasks/views/session_views.py b/tasks/views/session_views.py
index 6a7a3e981..3eaf45363 100644
--- a/tasks/views/session_views.py
+++ b/tasks/views/session_views.py
@@ -4,10 +4,9 @@
 from django.urls import reverse
 from django.http import HttpResponseRedirect
 from django.utils.translation import ugettext_lazy as _
-from django.forms import ModelForm
 
 from main.views import AllowErrorsOnBackbuttonMixin, UpdateView, DeleteView, CreateView
-from ..forms import SessionUpdateForm, SessionEndForm
+from ..forms import SessionUpdateForm, SessionEndForm, SessionOverviewForm
 from ..models import Session, Study
 
 
@@ -45,18 +44,10 @@ def delete(self, request, *args, **kwargs):
 ##################
 
 
-class HiddenForm(ModelForm):
-    """This is needed to make the navigation work on this information page."""
-
-    class Meta:
-        model = Study
-        fields = []
-
-
 class SessionStart(AllowErrorsOnBackbuttonMixin, UpdateView):
 
     model = Study
-    form_class = HiddenForm
+    form_class = SessionOverviewForm
     template_name = "tasks/session_start.html"
 
     def get_next_url(self):
@@ -159,7 +150,7 @@ def get_back_url(self):
 class SessionOverview(AllowErrorsOnBackbuttonMixin, UpdateView):
 
     model = Study
-    form_class = HiddenForm
+    form_class = SessionOverviewForm
     template_name = "tasks/session_overview.html"
 
     def get_context_data(self, **kwargs):