diff --git a/activities/views.py b/activities/views.py
index acf2a5f..a2b4a0e 100644
--- a/activities/views.py
+++ b/activities/views.py
@@ -8,6 +8,7 @@ from django.views.generic import DetailView, ListView, View
 from django.views.generic.detail import SingleObjectMixin
 
 from people import models as people_models
+from people import permissions
 from . import models
 
 
@@ -54,20 +55,23 @@ class ActivityDetailView(DetailView):
         return context
 
 
-class ActivityAttendanceView(SingleObjectMixin, View):
+class ActivityAttendanceView(permissions.UserIsLinkedPersonMixin, SingleObjectMixin, View):
     """
     View to add or delete attendance of an activity.
     """
     model = models.Activity
 
+    def get_test_person(self) -> people_models.Person:
+        data = json.loads(self.request.body)
+
+        self.person = people_models.Person.objects.get(pk=data['pk'])
+        return self.person
+
     def post(self, request, *args, **kwargs):
         self.object = self.get_object()
 
         if request.is_ajax():
-            data = json.loads(request.body)
-
-            person = people_models.Person.objects.get(pk=data['pk'])
-            self.object.attendance_list.add(person)
+            self.object.attendance_list.add(self.person)
 
             return HttpResponse(status=204)
 
@@ -77,10 +81,7 @@ class ActivityAttendanceView(SingleObjectMixin, View):
         self.object = self.get_object()
 
         if request.is_ajax():
-            data = json.loads(request.body)
-
-            person = people_models.Person.objects.get(pk=data['pk'])
-            self.object.attendance_list.remove(person)
+            self.object.attendance_list.remove(self.person)
 
             return HttpResponse(status=204)
 
diff --git a/breccia_mapper/templates/403.html b/breccia_mapper/templates/403.html
new file mode 100644
index 0000000..f142b39
--- /dev/null
+++ b/breccia_mapper/templates/403.html
@@ -0,0 +1,7 @@
+{% extends 'base.html' %}
+
+{% block content %}
+    <h2>Error 403 at {{ request.path }}</h2>
+
+    <p>{{ exception }}</p>
+{% endblock content %}
\ No newline at end of file
diff --git a/people/permissions.py b/people/permissions.py
new file mode 100644
index 0000000..a9edb85
--- /dev/null
+++ b/people/permissions.py
@@ -0,0 +1,33 @@
+"""
+Permission mixins for views relating to :class:`Person`s.
+"""
+
+from django.contrib.auth.mixins import UserPassesTestMixin
+
+from . import models
+
+
+class UserIsLinkedPersonMixin(UserPassesTestMixin):
+    """
+    Grant access if the user is staff or has a :class:`Person` record and
+    this is the one referred to in the view.
+    """
+    related_person_field = None
+    permission_denied_message = 'You do not have permission to view this page.'
+
+    def get_test_person(self) -> models.Person:
+        """
+        Get the :class:`Person` to test the user against.
+        """
+        if self.related_person_field is None:
+            test_person = self.get_object()
+
+            if not isinstance(test_person, models.Person):
+                raise AttributeError('View incorrectly configured: \'related_person_field\' must be defined.')
+
+            return test_person
+
+        return getattr(self.get_object(), self.related_person_field)
+
+    def test_func(self) -> bool:
+        return self.request.user.is_staff or self.get_test_person() == self.request.user.person
diff --git a/people/views.py b/people/views.py
index 3a674e2..581b0e6 100644
--- a/people/views.py
+++ b/people/views.py
@@ -5,7 +5,7 @@ Views for displaying or manipulating models in the 'people' app.
 from django.http import HttpResponseRedirect
 from django.views.generic import CreateView, DetailView, ListView, UpdateView
 
-from . import forms, models
+from . import forms, models, permissions
 
 
 class PersonCreateView(CreateView):
@@ -33,7 +33,7 @@ class PersonListView(ListView):
     template_name = 'people/person/list.html'
 
 
-class ProfileView(DetailView):
+class ProfileView(permissions.UserIsLinkedPersonMixin, DetailView):
     """
     View displaying the profile of a :class:`Person` - who may be a user.
     """
@@ -50,10 +50,11 @@ class ProfileView(DetailView):
             return super().get_object(queryset)
 
         except AttributeError:
+            # pk was not provided in URL
             return self.request.user.person
 
 
-class PersonUpdateView(UpdateView):
+class PersonUpdateView(permissions.UserIsLinkedPersonMixin, UpdateView):
     """
     View for updating a :class:`Person` record.
     """
@@ -62,15 +63,16 @@ class PersonUpdateView(UpdateView):
     form_class = forms.PersonForm
 
 
-class RelationshipDetailView(DetailView):
+class RelationshipDetailView(permissions.UserIsLinkedPersonMixin, DetailView):
     """
     View displaying details of a :class:`Relationship`.
     """
     model = models.Relationship
     template_name = 'people/relationship/detail.html'
+    related_person_field = 'source'
 
 
-class RelationshipCreateView(CreateView):
+class RelationshipCreateView(permissions.UserIsLinkedPersonMixin, CreateView):
     """
     View for creating a :class:`Relationship`.
 
@@ -80,6 +82,15 @@ class RelationshipCreateView(CreateView):
     template_name = 'people/relationship/create.html'
     form_class = forms.RelationshipForm
 
+    def get_test_person(self) -> models.Person:
+        """
+        
+        """
+        if self.request.method == 'POST':
+            return models.Person.objects.get(pk=self.request.POST.get('source'))
+        
+        return models.Person.objects.get(pk=self.kwargs.get('person_pk'))
+
     def get(self, request, *args, **kwargs):
         self.person = models.Person.objects.get(pk=self.kwargs.get('person_pk'))