diff --git a/app/controllers/memberships_controller.rb b/app/controllers/memberships_controller.rb
new file mode 100644
index 00000000..7ddba3bf
--- /dev/null
+++ b/app/controllers/memberships_controller.rb
@@ -0,0 +1,63 @@
+class MembershipsController < ApplicationController
+  before_action :set_group
+  before_action :assure_admin
+
+  # PATCH /groups/1/remove_user or /groups/1/remove_user.json
+  def remove_user
+    user = User.find(params[:user])
+    respond_to do |format|
+      if user.memberships.destroy_by(group: @group)
+        respond_with_notice(format, redirect: edit_group_path(@group), notice: t(:group_user_removed))
+      else
+        unprocessable_response(format, redirect: :edit, entity: @group)
+      end
+    end
+  end
+
+  # PATCH /groups/1/add_user or /groups/1/add_user.json
+  def add_user
+    respond_to do |format|
+      user = User.where(email: params[:user][:email]).first
+      if user.blank?
+        respond_with_alert(format, redirect: edit_group_url(@group), alert: t(:group_user_not_found))
+      elsif Membership.where(user: user, group: @group, role: :member).first_or_create
+        respond_with_notice(format, redirect: edit_group_url(@group), notice: t(:group_user_added))
+      else
+        unprocessable_response(format, redirect: :edit, entity: @group)
+      end
+    end
+  end
+
+  private
+
+  def assure_signed_in
+    unless user_signed_in?
+      redirect_to new_user_session_path, notice: t(:login_first)
+      return false
+    end
+    true
+  end
+
+  def assure_admin
+    assure_signed_in
+    unless current_user.admin_in? @group
+      redirect_to groups_url, notice: t(:only_admins)
+      return false
+    end
+    true
+  end
+
+  def set_group
+    @group = Group.find(params[:group_id])
+  end
+
+  def respond_with_notice(format, redirect:, notice:)
+    format.html { redirect_to redirect, notice: notice }
+    format.json { head :no_content }
+  end
+
+  def respond_with_alert(format, redirect:, alert:)
+    format.html { redirect_to redirect, alert: alert }
+    format.json { head :no_content }
+  end
+end
diff --git a/app/views/groups/_modal-add-member.html.erb b/app/views/groups/_modal-add-member.html.erb
new file mode 100644
index 00000000..b8ca7535
--- /dev/null
+++ b/app/views/groups/_modal-add-member.html.erb
@@ -0,0 +1,23 @@
+<div class="modal fade" id="addMemberGroupModal" tabindex="-1" aria-labelledby="addMemberGroupModalLabel" aria-hidden="true">
+  <div class="modal-dialog modal-dialog-centered">
+    <div class="modal-content">
+      <div class="modal-header border-0">
+        <h5 class="modal-title" id="addMemberGroupModalLabel"><%= t(:group_add_member) %></h5>
+        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="<%= t(:cancel) %>"></button>
+      </div>
+      <div class="modal-body">
+      <%= form_with(model: User.new, url: group_add_user_path(@group), method: :patch, local: true) do |form| %>
+        <div>
+          <%= form.label :email, t(:group_add_member_prompt), class: "form-label" %>
+          <%= form.email_field :email, placeholder: t(:member_email_placeholder), class: "form-control" %>
+          
+          <div class="modal-footer border-0 justify-content-evenly">
+            <button type="button" class="btn btn-secondary" data-bs-dismiss="modal"><%= t(:cancel) %></button>
+            <%= form.submit t(:group_add_member), :class => "btn btn-primary" %>
+          </div>
+        </div>
+      <% end %>
+      </div>
+    </div>
+  </div>
+</div>
diff --git a/app/views/groups/_modal-delete.html.erb b/app/views/groups/_modal-delete.html.erb
index ec2f1b87..b3f9581c 100644
--- a/app/views/groups/_modal-delete.html.erb
+++ b/app/views/groups/_modal-delete.html.erb
@@ -12,7 +12,6 @@
         <button type="button" class="btn btn-secondary" data-bs-dismiss="modal"><%= t(:cancel) %></button>
         <%= button_to t(:delete_group), group, method: :delete, class: "btn btn-primary" %>
       </div>
-       
     </div>
   </div>
-</div>
\ No newline at end of file
+</div>
diff --git a/app/views/groups/edit.html.erb b/app/views/groups/edit.html.erb
index 584a8060..2d105525 100644
--- a/app/views/groups/edit.html.erb
+++ b/app/views/groups/edit.html.erb
@@ -24,19 +24,26 @@
     <tr>
       <td><%= user.full_name %></td>
       <td><%= user.email %></td>
+      <% if not user.admin_in?(@group) %>
       <td>
         <%= mail_to user.email, class: "btn btn-sm btn-secondary" do %>
           <i class="bi bi-chat-fill"></i>
         <% end %>
-        <a href="#" class="btn btn-sm btn-primary"><i class="bi bi-person-dash-fill"></i></a>
+        <%= button_to group_remove_user_path(@group), method: :patch, params: {group: @group, user: user}, class: "btn btn-sm btn-primary", form: {class: "d-inline"} do %>
+          <i class="bi bi-person-dash-fill"></i>
+        <% end %>
       </td>
+      <% end %>
     </tr>
     <% end %>
   </tbody>
 </table>
 
 <div class="d-flex justify-content-center">
-  <%= link_to t(:group_add_member), "", class: "btn btn-secondary mx-1" %>
+  <button type="button" class="btn btn-secondary mx-1" data-bs-toggle="modal" data-bs-target="#addMemberGroupModal">
+    <%= t(:group_add_member) %>
+  </button>
+  <%= render "modal-add-member", group: @group %>
 
   <button type="button" class="btn btn-primary mx-1" data-bs-toggle="modal" data-bs-target="#deleteGroupModal">
     <%= t(:delete_group) %>
diff --git a/config/locales/views/groups/de.yml b/config/locales/views/groups/de.yml
index 3cbebc27..7997b71c 100644
--- a/config/locales/views/groups/de.yml
+++ b/config/locales/views/groups/de.yml
@@ -9,7 +9,9 @@ de:
   delete_group: "Gruppe löschen"
   leave_group: "Gruppe verlassen"
   edit_group: "Gruppe bearbeiten"
+
   group_add_member: "Nutzer hinzufügen"
+  group_add_member_prompt: "Bitte geben Sie die E-Mail-Adresse des Nutzers ein, den Sie zur Gruppe hinzufügen möchten."
   group_no_items: "Keine Items vorhanden"
 
   group_name : "Gruppenname"
@@ -22,6 +24,7 @@ de:
 
   member_name: "Name"
   member_email: "E-Mail"
+  member_email_placeholder: "beispiel.benutzer@hpi.de"
 
   login_first: "Sie müssen sich erst anmelden"
   only_admins: "Nur Administratoren dürfen diese Gruppe bearbeiten"
@@ -29,3 +32,7 @@ de:
   group_new: "Die Gruppe wurde erfolgreich erstellt"
   group_update: "Die Gruppe wurde erfolgreich aktualisiert"
   group_destroy: "Die Gruppe wurde wurde erfolgreich gelöscht"
+
+  group_user_not_found: "Dieser Nutzer konnte nicht gefunden werden"
+  group_user_added: "Nutzer wurde hinzugefügt"
+  group_user_removed: "Nutzer wurde entfernt"
diff --git a/config/locales/views/groups/en.yml b/config/locales/views/groups/en.yml
index a73c5e39..e08486cb 100644
--- a/config/locales/views/groups/en.yml
+++ b/config/locales/views/groups/en.yml
@@ -9,7 +9,9 @@ en:
   delete_group: "Delete group"
   leave_group: "Leave group"
   edit_group: "Edit group"
+
   group_add_member: "Add user"
+  group_add_member_prompt: "Please provide the email address of the user you'd like to add to this group."
   group_no_items: "No items present"
 
   group_name : "Groupname"
@@ -22,6 +24,7 @@ en:
 
   member_name: "Name"
   member_email: "E-mail"
+  member_email_placeholder: "example.user@hpi.de"
 
   login_first: "You have to log in first"
   only_admins: "Only admins are allowed to edit this group"
@@ -29,3 +32,8 @@ en:
   group_new: "Group has been created successfully"
   group_update: "Group has been updated successfully"
   group_destroy: "Group has been deleted successfully"
+
+  group_user_not_found: "This user could not be found"
+  group_user_added: "User was successfully added"
+  group_user_removed: "User was successfully removed"
+  
\ No newline at end of file
diff --git a/config/routes.rb b/config/routes.rb
index 476eea6e..cad61d45 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -5,7 +5,10 @@
   # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
   resources :groups, except: [:show, :new] do
     post :leave
+    patch :add_user, to: "memberships#add_user"
+    patch :remove_user, to: "memberships#remove_user"
   end
+
   resources :items do
     patch :reserve
     patch :borrow