diff --git a/Gemfile b/Gemfile
index fd56b94..b9a3950 100644
--- a/Gemfile
+++ b/Gemfile
@@ -48,6 +48,7 @@ gem "tzinfo-data", platforms: %i[windows jruby]
 gem "bootsnap", require: false
 
 # Use Active Storage variants [https://guides.rubyonrails.org/active_storage_overview.html#transforming-images]
+gem "activerecord-enhancedsqlite3-adapter"
 gem "bootstrap_form"
 gem "caxlsx"
 gem "caxlsx_rails"
@@ -58,7 +59,7 @@ gem "pandoc-ruby"
 gem "prawn-markup"
 gem "prawn-rails"
 gem "sablon"
-gem "activerecord-enhancedsqlite3-adapter"
+gem "ransack"
 gem "slim"
 
 group :development, :test do
diff --git a/Gemfile.lock b/Gemfile.lock
index 975d209..18ac919 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -258,6 +258,10 @@ GEM
       zeitwerk (~> 2.6)
     rainbow (3.1.1)
     rake (13.2.1)
+    ransack (4.2.1)
+      activerecord (>= 6.1.5)
+      activesupport (>= 6.1.5)
+      i18n
     rbs (3.5.2)
       logger
     rdoc (6.7.0)
@@ -396,6 +400,7 @@ DEPENDENCIES
   prawn-rails
   puma (>= 5.0)
   rails (~> 7.2)
+  ransack
   rubocop
   rubocop-capybara
   rubocop-rails
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 7ebfbf9..6bd9db2 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -18,4 +18,10 @@ module ApplicationHelper
       safe_join(fields)
     end
   end
+
+  def safe_display(value, &block)
+    return unless value
+
+    yield(value)
+  end
 end
diff --git a/app/models/check.rb b/app/models/check.rb
index 1caf36a..812ee87 100644
--- a/app/models/check.rb
+++ b/app/models/check.rb
@@ -52,16 +52,26 @@ class Check < ApplicationRecord
                         :standard_text,
                         :powerpoint_text
 
+  after_create { update(number: id) }
+
   scope(:search, lambda do |term|
     # TODO: Search only fields for current locale.
     joins("INNER JOIN action_text_rich_texts ON action_text_rich_texts.record_id = checks.id AND record_type = 'Check'").where("checks.name_de LIKE :term OR checks.name_de LIKE :term OR action_text_rich_texts.body LIKE :term", term: "%#{term}%").distinct
   end)
 
+  def self.ransackable_attributes(auth_object = nil)
+    [ "applicable_to_app", "applicable_to_web", "auditory", "cognitive", "conformity_level", "created_at", "external_number", "external_url", "id", "level", "manual_test", "name", "name_de", "name_en", "number", "physical", "position", "principle_id", "priority", "test_url", "updated_at", "visual" ]
+  end
+
+  def self.ransackable_associations(auth_object = nil)
+    [ "links", "principle", "rich_text_comment", "rich_text_conformity_notice_de", "rich_text_conformity_notice_en", "rich_text_criterion_de", "rich_text_criterion_details_de", "rich_text_criterion_details_en", "rich_text_criterion_en", "rich_text_example_de", "rich_text_example_en", "rich_text_exemption_details_de", "rich_text_exemption_details_en", "rich_text_powerpoint_text_de", "rich_text_powerpoint_text_en", "rich_text_quick_criterion_de", "rich_text_quick_criterion_en", "rich_text_quick_fail_de", "rich_text_quick_fail_en", "rich_text_quick_fix_de", "rich_text_quick_fix_en", "rich_text_standard_text_de", "rich_text_standard_text_en", "rich_text_test_instructions", "standards" ]
+  end
+
   def display_target_disabilities
-    %i[visual auditory physical cognitive].select { |d| send(:"#{d}?") }.map { |d| I18n.t("disability.#{d}") }.map(&:first).join(", ")
+    %i[visual auditory physical cognitive].select { |d| send(:"#{d}?") }.map { |d| I18n.t("disability.#{d}") }.join(", ")
   end
 
   def display_applicabilities
-    %i[applicable_to_app applicable_to_web].select { |a| send(:"#{a}?") }.map { |a| I18n.t("applicability.#{a}") }.map(&:first).join(", ")
+    %i[applicable_to_app applicable_to_web].select { |a| send(:"#{a}?") }.map { |a| I18n.t("applicability.#{a}") }.join(", ")
   end
 end
diff --git a/app/views/checks/_check.html.slim b/app/views/checks/_check.html.slim
index 79f9a08..6669710 100644
--- a/app/views/checks/_check.html.slim
+++ b/app/views/checks/_check.html.slim
@@ -4,15 +4,15 @@ div id=dom_id(check)
       tr 
         th = Check.human_attribute_name(:id)
         td = check.id
-      tr 
-        th = Principle.model_name.human
-        td = check.principle&.t_name
-      tr
-        th = Check.human_attribute_name(:number)
-        td = check.number
       tr
         th = Check.human_attribute_name(:name)
         td = check.t_name
+      tr
+        th = Check.human_attribute_name(:number)
+        td = check.number
+      tr 
+        th = Principle.model_name.human
+        td = check.principle&.t_name
       tr
         th = Standard.model_name.human(count: check.standard_ids.size)
         td = check.standards.map(&:t_name).join(", ")
@@ -25,36 +25,48 @@ div id=dom_id(check)
       tr
         th = Check.human_attribute_name(:external_number)
         td = check.external_number
+      tr
+        th = Check.human_attribute_name(:external_url)
+        td = check.external_url
       tr
         th = Check.human_attribute_name(:conformity_level)
         td = check.conformity_level
       tr 
         th = Check.human_attribute_name(:conformity_notice_de)
         td = check.conformity_notice_de
-      tr 
-        th = Check.human_attribute_name(:conformity_notice_en)
-        td = check.conformity_notice_en
       tr
         th = Check.human_attribute_name(:priority)
-        td = check.priority
+        td = safe_display(check.priority) { I18n.t("priority.#{_1}") }
       tr
         th = Check.human_attribute_name(:quick_criterion_de)
         td = check.quick_criterion_de
-      tr
-        th = Check.human_attribute_name(:quick_criterion_en)
-        td = check.quick_criterion_en
       tr
         th = Check.human_attribute_name(:quick_fail_de)
         td = check.quick_fail_de
-      tr
-        th = Check.human_attribute_name(:quick_fail_en)
-        td = check.quick_fail_en
       tr
         th = Check.human_attribute_name(:quick_fix_de)
         td = check.quick_fix_de
       tr
-        th = Check.human_attribute_name(:quick_fix_en)
-        td = check.quick_fix_en
+        th = Check.human_attribute_name(:criterion_de)
+        td = check.criterion_de
+      tr
+        th = Check.human_attribute_name(:criterion_details_de)
+        td = check.criterion_details_de
+      tr
+        th = Check.human_attribute_name(:example_de)
+        td = check.example_de
+      tr
+        th = Check.human_attribute_name(:exemption_details_de)
+        td = check.exemption_details_de
+      tr
+        th = Check.human_attribute_name(:test_instructions)
+        td = check.test_instructions
+      tr
+        th = Check.human_attribute_name(:powerpoint_text_de)
+        td = check.powerpoint_text_de
+      tr
+        th = Check.human_attribute_name(:comment)
+        td = check.comment
       tr 
         th = Link.model_name.human(count: check.links.size)
         td
diff --git a/app/views/checks/_form.html.slim b/app/views/checks/_form.html.slim
index 64cb873..cbdc5cc 100644
--- a/app/views/checks/_form.html.slim
+++ b/app/views/checks/_form.html.slim
@@ -5,23 +5,26 @@
   .row
     = form.collection_radio_buttons(:principle_id, Principle.all.sort_by(&:t_name), :id, :t_name) { |b| b.label(class: "col-md-2") { b.radio_button + b.text } }
   = form.collection_check_boxes :standard_ids, Standard.all.sort_by{ _1.t_name.downcase }, :id, :t_name, include_blank: true 
+  
   h2 Zugänglichkeit
   .row
     - %w[visual auditory physical cognitive].sort_by { |d| t("disability.#{d}") }.each do |d|
       .col-md-3
         = form.check_box d, label: t("disability.#{d}").capitalize
+  
   h2 Anwendbarkeit
   .row
     - %w[applicable_to_web applicable_to_app].sort_by { |d| t("applicability.#{d}") }.each do |d|
       .col-md-6
         = form.check_box d, label: t("applicability.#{d}").capitalize
+  
   h2 Richtlinie
   = form.text_field :external_number
   = form.text_field :external_url
   = form.select :conformity_level, Check.conformity_levels.keys, include_blank: true
   = multilang_form_field(form, :conformity_notice, as: :rich_text_area)
-  
   = form.select :priority, Check.priorities.keys.map{ [t("priority.#{_1}"), _1] }, include_blank: true
+  
   h2 Quick Infos
   = multilang_form_field(form, :quick_criterion, as: :rich_text_area)
   = multilang_form_field(form, :quick_fail, as: :rich_text_area)
diff --git a/app/views/checks/index.html.slim b/app/views/checks/index.html.slim
index 830ab44..b21cd0e 100644
--- a/app/views/checks/index.html.slim
+++ b/app/views/checks/index.html.slim
@@ -1,5 +1,16 @@
 h1
   = t("scaffold.pagetitle_index", model: Check.model_name.human(count: 2))
+
+/= search_form_for @q do |f|
+  = f.search_field :name_cont
+  /= f.select :principle_id_in, options_from_collection_for_select(Principle.all.sort_by(&:name_de), :id, :name_de, filter_params[:principle_id_in]), { include_blank: false }, { multiple: true, class: "form-select" }
+  = f.label :principle_id_in, "Prinzip"
+  .d-flex.flex-row.mb-3
+    - Principle.all.sort_by(&:name_de).each do |principle|
+      .me-3
+        = f.check_box :principle_id_in, checked: @q[:principle_id_in].include?(principle.id), label: principle.name_de, id: "principle_id_in_#{principle.id}"
+  = f.submit
+
 = bootstrap_form_with(url: checks_path(page: params[:page]), method: :get, scope: :filter) do |form|
   = form.hidden_field :page, value: params[:page] if params[:page]
   .row
diff --git a/config/application.rb b/config/application.rb
index 3160f19..1c88341 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -1,5 +1,7 @@
 require_relative 'boot'
 
+ENV['RANSACK_FORM_BUILDER'] = '::BootstrapForm::FormBuilder'
+
 require 'rails'
 # Pick the frameworks you want:
 require 'active_model/railtie'
diff --git a/db/migrate/20240820164827_finalize_check_fields.rb b/db/migrate/20240820164827_finalize_check_fields.rb
index 488070e..da931d9 100644
--- a/db/migrate/20240820164827_finalize_check_fields.rb
+++ b/db/migrate/20240820164827_finalize_check_fields.rb
@@ -1,7 +1,6 @@
 class FinalizeCheckFields < ActiveRecord::Migration[7.2]
   def change
-    add_column :checks, :number, :integer
-    add_index :checks, :number, unique: true
+    add_column :checks, :number, :string
     
     add_column :checks, :name_de, :string
     add_column :checks, :name_en, :string
@@ -23,6 +22,6 @@ class FinalizeCheckFields < ActiveRecord::Migration[7.2]
     add_column :checks, :manual_test, :boolean, null: false, default: true
     add_column :checks, :test_url, :string, null: true
 
-    add_column :checks, :external_url, :string, null: true
+    add_column :checks, :external_url, :string, null: false
   end
 end