diff --git a/castellum/contacts/templates/contacts/__guardian_item.html b/castellum/contacts/templates/contacts/__guardian_item.html
index 82fbd160aa4063f5476f9079bad77e2d5e653d4c..25285b53ef6cbf9168fc54fa661704570d894ef3 100644
--- a/castellum/contacts/templates/contacts/__guardian_item.html
+++ b/castellum/contacts/templates/contacts/__guardian_item.html
@@ -1,4 +1,4 @@
-{% load i18n auth %}
+{% load i18n recruitment %}
 
 <div class="rounded-lg border bg-light p-3 mb-2 d-flex align-items-center {% if removed %}text-muted{% endif %}" data-js="guardian-wrapper">
     <div class="flex-grow-1">
@@ -10,9 +10,16 @@
             <input id="id_{{ name }}_{{ pk }}" type="hidden" name="{{ name }}" value="{{ pk }}" {% if removed %}disabled{% endif %}>
         {% endif %}
     </div>
-    {% has_perm 'subjects.view_subject' user as can_view_subject %}
-    {% if slug and can_view_subject %}
-        <a href="{% url 'subjects:detail' slug %}" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
+    {% if guardian %}
+        {% if view.context == 'subject_management' %}
+            <a href="{% url 'subjects:detail' guardian.slug %}" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
+        {% elif view.context == 'recruitment' %}
+            {% study_guardian_hash study guardian as hash %}
+            <a href="{% url 'recruitment:guardian-contact-update' study.pk participation.pk hash %}" target="_blank" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
+        {% elif view.context == 'execution' %}
+            {% study_guardian_hash study guardian as hash %}
+            <a href="{% url 'execution:guardian-contact-update' study.pk participation.pk hash %}" target="_blank" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
+        {% endif %}
     {% endif %}
     <button type="button" class="btn btn-sm btn-danger" {% if removed %}hidden{% endif %} data-js="guardian-remove">{% translate 'Remove' %}</button>
     <button type="button" class="btn btn-sm btn-outline-danger" {% if not removed %}hidden{% endif %} data-js="guardian-restore">{% translate 'Restore' %}</button>
diff --git a/castellum/contacts/templates/contacts/contact_form.html b/castellum/contacts/templates/contacts/contact_form.html
index d0856e847951b54c15a5e44a473a6ab32673fa8a..7daa4d63eda55fda2ce6f7426e9f9306c13597d0 100644
--- a/castellum/contacts/templates/contacts/contact_form.html
+++ b/castellum/contacts/templates/contacts/contact_form.html
@@ -1,5 +1,5 @@
 {% extends view.base_template|default:"subjects/base.html" %}
-{% load static i18n auth bootstrap4 %}
+{% load static i18n auth recruitment bootstrap4 %}
 
 {% block title %}
     {% if object %}
@@ -42,7 +42,7 @@
                 </template>
 
                 {% for widget in form.guardians_remove %}
-                    {% include 'contacts/__guardian_item.html' with name=form.guardians_remove.name pk=widget.data.value label=widget.choice_label slug=widget.choice_label.subject.slug removed=widget.data.selected %}
+                    {% include 'contacts/__guardian_item.html' with name=form.guardians_remove.name pk=widget.data.value label=widget.choice_label guardian=widget.choice_label.subject removed=widget.data.selected %}
                 {% endfor %}
 
                 {% for subject in form.cleaned_data.guardians_add %}
@@ -59,8 +59,14 @@
                             <div class="h5 mb-0">{{ contact }}</div>
                             <input type="hidden" name="guardians_remove" disabled>
                         </div>
-                        {% if can_view_subject %}
+                        {% if view.context == 'subject_management' %}
                             <a href="{% url 'subjects:detail' contact.subject.slug %}" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
+                        {% elif view.context == 'recruitment' %}
+                            {% study_guardian_hash study contact.subject as hash %}
+                            <a href="{% url 'recruitment:guardian-contact-update' study.pk participation.pk hash %}" target="_blank" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
+                        {% elif view.context == 'execution' %}
+                            {% study_guardian_hash study contact.subject as hash %}
+                            <a href="{% url 'execution:guardian-contact-update' study.pk participation.pk hash %}" target="_blank" class="btn btn-sm btn-outline-primary mx-1">{% translate 'Details' %}</a>
                         {% endif %}
                     </div>
                 {% endfor %}
diff --git a/castellum/execution/urls.py b/castellum/execution/urls.py
index 0e34dd7dbeea367383d9ac8d3adc656267fb6a44..dfc453e5e570d71829f7167418f2d1e86a8a0e4d 100644
--- a/castellum/execution/urls.py
+++ b/castellum/execution/urls.py
@@ -36,6 +36,7 @@ from .views import ContactUpdateView
 from .views import DataProtectionUpdateView
 from .views import ExclusionCriteriaView
 from .views import ExportView
+from .views import GuardianContactUpdateView
 from .views import NewsMailView
 from .views import ParticipationAppointmentsUpdateView
 from .views import ParticipationDetailView
@@ -116,6 +117,11 @@ urlpatterns = [
         AdditionalInfoUpdateView.as_view(),
         name='additional-info-update',
     ),
+    path(
+        '<int:study_pk>/<int:participation_pk>/guardians/<hash>/update-contact/',
+        GuardianContactUpdateView.as_view(),
+        name='guardian-contact-update',
+    ),
 ]
 
 if settings.CASTELLUM_PSEUDONYMS_API_ENABLED:
diff --git a/castellum/execution/views.py b/castellum/execution/views.py
index 44ba07f659ce73854166ef79e1d7e0f467715e14..b694cf28c882aba952af738fb9f0dc76762ac343 100644
--- a/castellum/execution/views.py
+++ b/castellum/execution/views.py
@@ -27,6 +27,7 @@ from django.contrib import messages
 from django.core.exceptions import ObjectDoesNotExist
 from django.core.exceptions import PermissionDenied
 from django.db import models
+from django.http import Http404
 from django.http import HttpResponse
 from django.shortcuts import get_object_or_404
 from django.shortcuts import redirect
@@ -57,10 +58,12 @@ from castellum.recruitment.models import ExecutionTag
 from castellum.recruitment.models import NewsMailBatch
 from castellum.recruitment.models import Participation
 from castellum.recruitment.models import ReliabilityEntry
+from castellum.recruitment.templatetags.recruitment import study_guardian_hash
 from castellum.studies.mixins import StudyMixin
 from castellum.studies.models import Study
 from castellum.subjects.mixins import BaseAdditionalInfoUpdateView
 from castellum.subjects.mixins import BaseDataProtectionUpdateView
+from castellum.subjects.mixins import SubjectMixin
 from castellum.subjects.models import Subject
 from castellum.utils.mail import MailContext
 
@@ -474,6 +477,7 @@ class ExecutionUpdateMixin(ParticipationMixin):
 
 class ContactUpdateView(ExecutionUpdateMixin, BaseContactUpdateView):
     subtab = 'contact'
+    context = 'execution'
 
     def get_object(self):
         return self.participation.subject.contact
@@ -608,3 +612,36 @@ class TagView(StudyMixin, PermissionRequiredMixin, TemplateView):
             tag.delete()
             messages.success(request, _('Tag has been deleted.'))
             return redirect('execution:execution-tags', self.study.pk)
+
+
+class GuardianContactUpdateView(StudyMixin, SubjectMixin, BaseContactUpdateView):
+    base_template = 'execution/base.html'
+    study_status = [Study.EXECUTION]
+
+    def get_success_url(self):
+        return self.request.path
+
+    def form_valid(self, form, *args):
+        messages.success(self.request, _('Data has been saved.'))
+        return super().form_valid(form, *args)
+
+    def get_permission_required(self):
+        permission_required = {'recruitment.conduct_study'}
+        permission_required.update(super().get_permission_required())
+        return permission_required
+
+    def get_object(self):
+        participation = get_object_or_404(
+            Participation,
+            pk=self.kwargs['participation_pk'],
+            study=self.study,
+            status=Participation.INVITED,
+        )
+        if not self.request.user.has_privacy_level(participation.subject.privacy_level):
+            return self.handle_no_permission()
+
+        for guardian in participation.subject.contact.guardians.all():
+            if study_guardian_hash(self.study, guardian.subject) == self.kwargs['hash']:
+                return guardian
+
+        raise Http404
diff --git a/castellum/recruitment/templatetags/recruitment.py b/castellum/recruitment/templatetags/recruitment.py
new file mode 100644
index 0000000000000000000000000000000000000000..404d6b79964fc7b82e267c1db102a922ca1431f0
--- /dev/null
+++ b/castellum/recruitment/templatetags/recruitment.py
@@ -0,0 +1,34 @@
+# (c) 2018-2021
+#     MPIB <https://www.mpib-berlin.mpg.de/>,
+#     MPI-CBS <https://www.cbs.mpg.de/>,
+#     MPIP <http://www.psych.mpg.de/>
+#
+# This file is part of Castellum.
+#
+# Castellum is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Castellum is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public
+# License along with Castellum. If not, see
+# <http://www.gnu.org/licenses/>.
+
+import hashlib
+
+from django import template
+
+register = template.Library()
+
+
+@register.simple_tag
+def study_guardian_hash(study, subject):
+    m = hashlib.sha256()
+    m.update(str(study.pk).encode('ascii'))
+    m.update(subject.slug.encode('ascii'))
+    return m.hexdigest()
diff --git a/castellum/recruitment/urls.py b/castellum/recruitment/urls.py
index bac076d75048fddf9eff99cb8063a949f858212f..8d454a70c2275b831aed161a5d17fb2bf2773cb8 100644
--- a/castellum/recruitment/urls.py
+++ b/castellum/recruitment/urls.py
@@ -32,6 +32,7 @@ from .views import CalendarView
 from .views import ContactUpdateView
 from .views import ContactView
 from .views import DataProtectionUpdateView
+from .views import GuardianContactUpdateView
 from .views import MailRecruitmentCleanupView
 from .views import MailRecruitmentRemindView
 from .views import MailRecruitmentView
@@ -94,4 +95,9 @@ urlpatterns = [
         AdditionalInfoUpdateView.as_view(),
         name='additional-info-update',
     ),
+    path(
+        '<int:study_pk>/<int:participation_pk>/guardians/<hash>/update-contact/',
+        GuardianContactUpdateView.as_view(),
+        name='guardian-contact-update',
+    ),
 ]
diff --git a/castellum/recruitment/views.py b/castellum/recruitment/views.py
index 3307bdea9aa4791513966386feb6981e92106add..a3559f8d82f1e4c22a112145f655a6dca3350e1c 100644
--- a/castellum/recruitment/views.py
+++ b/castellum/recruitment/views.py
@@ -60,6 +60,7 @@ from castellum.studies.models import StudySession
 from castellum.studies.models import StudyTypeEventFeed
 from castellum.subjects.mixins import BaseAdditionalInfoUpdateView
 from castellum.subjects.mixins import BaseDataProtectionUpdateView
+from castellum.subjects.mixins import SubjectMixin
 from castellum.subjects.models import Subject
 from castellum.utils import cached_request
 from castellum.utils import contrast_color
@@ -75,6 +76,7 @@ from .mixins import get_recruitable
 from .models import MailBatch
 from .models import Participation
 from .models.attributes import get_description_by_statistics_rank
+from .templatetags.recruitment import study_guardian_hash
 
 logger = logging.getLogger(__name__)
 
@@ -524,6 +526,7 @@ class RecruitmentUpdateMixin(ParticipationMixin):
 
 class ContactUpdateView(RecruitmentUpdateMixin, BaseContactUpdateView):
     subtab = 'contact'
+    context = 'recruitment'
 
     def get_object(self):
         return self.participation.subject.contact
@@ -550,6 +553,36 @@ class AdditionalInfoUpdateView(RecruitmentUpdateMixin, BaseAdditionalInfoUpdateV
         return self.participation.subject
 
 
+class GuardianContactUpdateView(StudyMixin, SubjectMixin, BaseContactUpdateView):
+    base_template = 'recruitment/base.html'
+    study_status = [Study.EXECUTION]
+
+    def get_success_url(self):
+        return self.request.path
+
+    def form_valid(self, form, *args):
+        messages.success(self.request, _('Data has been saved.'))
+        return super().form_valid(form, *args)
+
+    def get_permission_required(self):
+        permission_required = {'recruitment.recruit'}
+        permission_required.update(super().get_permission_required())
+        return permission_required
+
+    def get_object(self):
+        participation = get_object_or_404(
+            Participation, pk=self.kwargs['participation_pk'], study=self.study
+        )
+        if not self.request.user.has_privacy_level(participation.subject.privacy_level):
+            return self.handle_no_permission()
+
+        for guardian in participation.subject.contact.guardians.all():
+            if study_guardian_hash(self.study, guardian.subject) == self.kwargs['hash']:
+                return guardian
+
+        raise Http404
+
+
 class CalendarView(StudyMixin, PermissionRequiredMixin, BaseCalendarView):
     model = Study
     permission_required = 'appointments.change_appointment'
diff --git a/castellum/subjects/views.py b/castellum/subjects/views.py
index 5854bf2904f41e7268b5cadc6ab5bf8478c06130..fec839eadf736a4332d6a81f60efff7a857627e2 100644
--- a/castellum/subjects/views.py
+++ b/castellum/subjects/views.py
@@ -346,6 +346,7 @@ class AdditionalInfoUpdateView(SubjectUpdateMixin, BaseAdditionalInfoUpdateView)
 
 class ContactUpdateView(SubjectUpdateMixin, BaseContactUpdateView):
     tab = 'contact'
+    context = 'subject_management'
 
     def get_object(self):
         subject = get_object_or_404(Subject, slug=self.kwargs['slug'])