diff --git a/Gemfile b/Gemfile
index 66baec53..022275b8 100644
--- a/Gemfile
+++ b/Gemfile
@@ -86,6 +86,7 @@ gem 'rubanok'
 gem 'after_commit_everywhere', '~> 1.0'
 gem 'aasm'
 gem 'que-web'
+gem 'nanoid'
 
 # database
 gem 'hairtrigger'
diff --git a/Gemfile.lock b/Gemfile.lock
index 97721a98..556f16e6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -377,6 +377,7 @@ GEM
     multi_xml (0.6.0)
     mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
+    nanoid (2.0.0)
     net-imap (0.4.9)
       date
       net-protocol
@@ -682,6 +683,7 @@ DEPENDENCIES
   memory_profiler
   mini_magick
   mobility
+  nanoid
   net-ssh
   nokogiri
   pg
diff --git a/app/assets/stylesheets/application.scss b/app/assets/stylesheets/application.scss
index e4c4d343..b0db7459 100644
--- a/app/assets/stylesheets/application.scss
+++ b/app/assets/stylesheets/application.scss
@@ -22,6 +22,7 @@ $form-feedback-icon-valid-color: $black;
 $component-active-bg: $magenta;
 $btn-white-space: nowrap;
 $font-weight-bolder: 700;
+$zindex-modal-backdrop: 0;
 
 $spacers: (
   2-plus: 0.75rem
@@ -328,13 +329,13 @@ svg {
   }
 }
 
-.custom-control-label {
-  font-weight: bold;
-}
-
 .designs {
   .design {
     margin-top: 1rem;
+
+    .custom-control-label {
+      font-weight: bold;
+    }
   }
 }
 
diff --git a/app/controllers/posts_controller.rb b/app/controllers/posts_controller.rb
index 057c3068..f241dfb1 100644
--- a/app/controllers/posts_controller.rb
+++ b/app/controllers/posts_controller.rb
@@ -15,6 +15,23 @@ class PostsController < ApplicationController
     { locale: locale }
   end
 
+  # @todo Mover a tu propio scope
+  def new_array
+    @value = params.require(:value).strip
+    @name = params.require(:name).strip
+    id = params.require(:id).strip
+
+    headers['HX-Trigger-After-Swap'] = 'htmx:resetForm'
+
+    render layout: false
+  end
+
+  def new_array_value
+    @value = params.require(:value).strip
+
+    render layout: false
+  end
+
   def index
     authorize Post
 
diff --git a/app/javascript/controllers/array_controller.js b/app/javascript/controllers/array_controller.js
new file mode 100644
index 00000000..66cc2290
--- /dev/null
+++ b/app/javascript/controllers/array_controller.js
@@ -0,0 +1,120 @@
+import { Controller } from "stimulus";
+
+export default class extends Controller {
+  static targets = ["item", "search", "current"];
+
+  connect() {
+    // TODO: Stimulus >1
+    this.newArrayValueURL = new URL(window.location.origin);
+    this.newArrayValueURL.pathname = this.element.dataset.arrayNewArrayValue;
+    this.originalValue = JSON.parse(this.element.dataset.arrayOriginalValue);
+  }
+
+  /*
+   * Al eliminar el ítem, buscamos por su ID y lo eliminamos del
+   * documento.
+   */
+  remove(event) {
+    // TODO: Stimulus >1
+    event.preventDefault();
+
+    this.itemTargets
+      .find((x) => x.id === event.target.dataset.removeTargetParam)
+      ?.remove();
+  }
+
+  /*
+   * Al buscar, eliminamos las tildes y mayúsculas para no depender de
+   * cómo se escribió.
+   *
+   * Luego buscamos eso en el valor limpio, ignorando los items que ya
+   * están activados.
+   *
+   * Si el término de búsqueda está vacío, volvemos a la lista original.
+   */
+  search(event) {
+    const needle = this.searchTarget.value
+      .normalize("NFD")
+      .replace(/[\u0300-\u036f]/g, "")
+      .toLowerCase()
+      .trim();
+
+    if (needle) {
+      for (const itemTarget of this.itemTargets) {
+        itemTarget.style.display =
+          itemTarget.querySelector("input")?.checked ||
+          itemTarget.dataset.searchableValue.includes(needle)
+            ? ""
+            : "none";
+      }
+    } else {
+      for (const itemTarget of this.itemTargets) {
+        itemTarget.style.display = "";
+      }
+    }
+  }
+
+  /*
+   * Obtiene el input de un elemento
+   *
+   * @param [HTMLElement]
+   * @return [HTMLElement,nil]
+   */
+  inputFrom(target) {
+    if (target.tagName === "INPUT") return target;
+
+    return target.querySelector("input");
+  }
+
+  /*
+   * Detecta si el item es o contiene un checkbox/radio activado.
+   *
+   * @param [HTMLElement]
+   * @return [Bool]
+   */
+  isChecked(itemTarget) {
+    return this.inputFrom(itemTarget)?.checked || false;
+  }
+
+  /*
+   * Al cancelar, se vuelve al estado original de la lista
+   */
+  cancel(event) {
+    for (const itemTarget of this.itemTargets) {
+      const input = this.inputFrom(itemTarget);
+
+      input.checked = this.originalValue.includes(itemTarget.dataset.value);
+    }
+  }
+
+  /*
+   * Al aceptar, se envía todo el listado de valores nuevos al _backend_
+   * para que devuelva la representación de cada ítem en HTML. Además,
+   * se guarda el nuevo valor como la lista original, para la próxima
+   * cancelación.
+   */
+  accept(event) {
+    this.currentTarget.innerHTML = "";
+    this.originalValue = [];
+
+    for (const itemTarget of this.itemTargets) {
+      if (!itemTarget.dataset.value) continue;
+      if (!this.isChecked(itemTarget)) continue;
+
+      this.originalValue.push(itemTarget.dataset.value);
+      this.newArrayValueURL.searchParams.set("value", itemTarget.dataset.value);
+
+      // TODO: Renderizarlas todas juntas
+      fetch(this.newArrayValueURL)
+        .then((response) => response.text())
+        .then((body) =>
+          this.currentTarget.insertAdjacentHTML("beforeend", body),
+        );
+    }
+
+    // TODO: Stimulus >1
+    this.element.dataset.arrayOriginalValue = JSON.stringify(
+      this.originalValue,
+    );
+  }
+}
diff --git a/app/javascript/controllers/modal_controller.js b/app/javascript/controllers/modal_controller.js
new file mode 100644
index 00000000..3a614b80
--- /dev/null
+++ b/app/javascript/controllers/modal_controller.js
@@ -0,0 +1,40 @@
+import { Controller } from "stimulus";
+
+export default class extends Controller {
+  static targets = ["modal", "backdrop"];
+
+  show(event = undefined) {
+    event?.preventDefault();
+
+    this.modalTarget.style.display = "block";
+    this.backdropTarget.style.display = "block";
+    this.modalTarget.setAttribute("role", "dialog");
+    this.modalTarget.setAttribute("aria-modal", true);
+    this.modalTarget.removeAttribute("aria-hidden");
+
+    window.document.body.classList.add("modal-open");
+
+    setTimeout(() => {
+      this.modalTarget.classList.add("show");
+      this.backdropTarget.classList.add("show");
+    }, 1);
+  }
+
+  hide(event = undefined) {
+    event?.preventDefault();
+
+    this.backdropTarget.classList.remove("show");
+    this.modalTarget.classList.remove("show");
+
+    this.modalTarget.setAttribute("aria-hidden", true);
+    this.modalTarget.removeAttribute("role");
+    this.modalTarget.removeAttribute("aria-modal");
+
+    setTimeout(() => {
+      this.modalTarget.style.display = "";
+      this.backdropTarget.style.display = "";
+    }, 500);
+
+    window.document.body.classList.remove("modal-open");
+  }
+}
diff --git a/app/javascript/etc/htmx_abort.js b/app/javascript/etc/htmx_abort.js
index 308d0315..75e497ba 100644
--- a/app/javascript/etc/htmx_abort.js
+++ b/app/javascript/etc/htmx_abort.js
@@ -5,3 +5,7 @@ document.addEventListener("turbolinks:click", () => {
     window.htmx.trigger(hx, "htmx:abort");
   }
 });
+
+document.addEventListener("htmx:resetForm", (event) => {
+  event.target.reset();
+});
diff --git a/app/javascript/packs/application.js b/app/javascript/packs/application.js
index e10e2b5d..c523b0f0 100644
--- a/app/javascript/packs/application.js
+++ b/app/javascript/packs/application.js
@@ -42,3 +42,4 @@ Turbolinks.start()
 ActiveStorage.start()
 
 window.htmx = require('htmx.org/dist/htmx.js')
+window.htmx.config.selfRequestsOnly = true;
diff --git a/app/lib/core_extensions/string/remove_diacritics.rb b/app/lib/core_extensions/string/remove_diacritics.rb
new file mode 100644
index 00000000..679db13d
--- /dev/null
+++ b/app/lib/core_extensions/string/remove_diacritics.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+module CoreExtensions
+  module String
+    # Elimina tildes
+    module RemoveDiacritics
+      def remove_diacritics
+        unicode_normalize(:nfd).gsub(/[^\x00-\x7F]/, '')
+      end
+    end
+  end
+end
diff --git a/app/models/metadata_new_array.rb b/app/models/metadata_new_array.rb
new file mode 100644
index 00000000..65993be2
--- /dev/null
+++ b/app/models/metadata_new_array.rb
@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+# Implementa la nueva interfaz de gestión de valores
+class MetadataNewArray < MetadataArray
+end
diff --git a/app/views/bootstrap/_btn.haml b/app/views/bootstrap/_btn.haml
new file mode 100644
index 00000000..1bbebb26
--- /dev/null
+++ b/app/views/bootstrap/_btn.haml
@@ -0,0 +1,13 @@
+-#
+  Un botón
+
+  @param :content [String] Contenido
+  @param :action [String] Acción de Stimulus
+  @param :target [String] Objetivo de Stimulus
+  @param [Hash] Atributos en bruto, con mayor prioridad que action y target
+:ruby
+  attributes = local_assigns.to_h.except(:content)
+  attributes[:data] ||= {}
+  attributes[:data][:action] ||= local_assigns[:action]
+  attributes[:data][:target] ||= local_assigns[:target]
+%button.btn.btn-secondary{ type: 'button', **attributes }= content
diff --git a/app/views/bootstrap/_custom_checkbox.haml b/app/views/bootstrap/_custom_checkbox.haml
index 0c3ff3a6..c8cd1b41 100644
--- a/app/views/bootstrap/_custom_checkbox.haml
+++ b/app/views/bootstrap/_custom_checkbox.haml
@@ -1,6 +1,10 @@
-- help_id = "#{id}_help"
+:ruby
+  help_id = "#{id}_help"
+  checkbox_attributes = local_assigns.slice(:id, :type, :name, :value, :required, :checked)
+  checkbox_attributes[:type] ||= 'checkbox'
 
 .custom-control.custom-checkbox
-  %input.custom-control-input{ id: id, type: 'checkbox', name: name, value: value, required: required }
+  %input.custom-control-input{ **checkbox_attributes }
   %label.custom-control-label{ for: id, aria: { describedby: help_id } }= content
-  %small.form-text.text-muted{ id: help_id }= yield
+  - if (block = yield).present?
+    %small.form-text.text-muted{ id: help_id }= block
diff --git a/app/views/bootstrap/_modal.haml b/app/views/bootstrap/_modal.haml
new file mode 100644
index 00000000..f6dafc2a
--- /dev/null
+++ b/app/views/bootstrap/_modal.haml
@@ -0,0 +1,39 @@
+-#
+  # Modal
+
+  @see {https://getbootstrap.com/docs/4.6/components/modal/}
+  @see {https://github.com/bullet-train-co/nice_partials/issues/99}
+  @param :id [String] El ID del modal
+  @param :modal_content_attributes [Hash] Atributos para el contenido del modal
+  @param :hide_actions [Array<String>] Acciones al ocultar el modal
+  @yield :ID_body Contenido
+  @yield :ID_header Contenido del header (opcional)
+  @yield :ID_footer Contenido del pie (opcional)
+  @example
+    = render 'bootstrap/modal', id: 'algo' do |partial|
+      - content_for :algo_header do
+        = 'título'
+      - content_for :algo_body do
+        = 'contenido'
+      - content_for :algo_footer do
+        = 'pie'
+
+:ruby
+  local_assigns[:hide_actions] ||= []
+  local_assigns[:hide_actions] << 'click->modal#hide'
+  local_assigns[:modal_content_attributes] ||= {}
+
+.modal.fade{ tabindex: -1, aria: { hidden: 'true' }, data: { target: 'modal.modal' } }
+  .modal-backdrop.fade{ data: { target: 'modal.backdrop', action: local_assigns[:hide_actions].join(' ') } }
+  .modal-dialog.modal-dialog-scrollable.modal-dialog-centered
+    .modal-content{ **local_assigns[:modal_content_attributes] }
+      - if (header = yield(:"#{id}_header")).present?
+        .modal-header= header
+
+      .modal-body= yield(:"#{id}_body")
+
+      .modal-footer.flex-nowrap
+        - if (footer = yield(:"#{id}_footer"))
+          = footer
+        - else
+          %button.btn.btn-secondary.m-0{ type: 'button', data: { action: 'modal#hide' } }= t('.close')
diff --git a/app/views/layouts/application.html.haml b/app/views/layouts/application.html.haml
index eaa15eb4..65d3f777 100644
--- a/app/views/layouts/application.html.haml
+++ b/app/views/layouts/application.html.haml
@@ -25,6 +25,7 @@
       = render 'layouts/breadcrumb'
       = render 'layouts/flash'
 
+      = yield(:post_form)
       = yield
 
       - if flash[:js]
diff --git a/app/views/posts/_new_array_value.haml b/app/views/posts/_new_array_value.haml
new file mode 100644
index 00000000..75c5bf4d
--- /dev/null
+++ b/app/views/posts/_new_array_value.haml
@@ -0,0 +1,2 @@
+.col
+  %p= value
diff --git a/app/views/posts/attribute_ro/_new_array.haml b/app/views/posts/attribute_ro/_new_array.haml
new file mode 100644
index 00000000..20a0a545
--- /dev/null
+++ b/app/views/posts/attribute_ro/_new_array.haml
@@ -0,0 +1,8 @@
+%tr{ id: attribute }
+  %th= post_label_t(attribute, post: post)
+  %td
+    - if metadata.value.respond_to? :each
+      - metadata.value.each do |v|
+        %span.badge.badge-primary= v
+    - else
+      %span.badge.badge-primary{ lang: locale, dir: dir }= metadata.value
diff --git a/app/views/posts/attributes/_new_array.haml b/app/views/posts/attributes/_new_array.haml
new file mode 100644
index 00000000..394345a6
--- /dev/null
+++ b/app/views/posts/attributes/_new_array.haml
@@ -0,0 +1,59 @@
+-#
+  Genera un listado de checkboxes entre los que se puede elegir para guardar
+:ruby
+  id = "#{base}_#{attribute}"
+  name = "#{base}[#{attribute}][]"
+  form_id = "form-#{Nanoid.generate}"
+
+%div{ data: { controller: 'modal array', 'array-original-value': metadata.value.to_json, 'array-new-array-value': site_posts_new_array_value_path(site) } }
+  .form-group
+    = hidden_field_tag name, ''
+    = label_tag id, post_label_t(attribute, post: post)
+    -# Mostramos la lista de valores actuales.
+
+      Al aceptar el modal, se vacía el listado y se completa en base a
+      renderizaciones con HTMX. Para poder hacer eso, tenemos que poder
+      acceder a todos los items dentro del modal (como array.item) y
+      enviar el valor al endpoint que devuelve uno por uno. Esto lo
+      tenemos disponible en Stimulus, pero queremos usar HTMX o técnica
+      similar para poder renderizar del lado del servidor.
+
+      Para poder cancelar, mantenemos el estado original y desactivamos
+      o activamos los ítemes según estén incluidos en esa lista o no.
+    .row.row-cols-1.row-cols-md-2{ data: { target: 'array.current' } }
+      - metadata.value.sort_by(&:remove_diacritics).each do |value|
+        = render 'posts/new_array_value', value: value
+
+    = render 'bootstrap/btn', content: t('.edit'), action: 'modal#show'
+
+  = render 'bootstrap/modal', id: id, modal_content_attributes: { class: 'h-100' }, hide_actions: ['array#cancel'] do
+    - content_for :"#{id}_header" do
+      .form-group.flex-grow-1.mb-0
+        = label_tag id, post_label_t(attribute, post: post)
+        %input.form-control{ data: { target: 'array.search', action: 'input->array#search' }, type: 'search', placeholder: t('.filter') }
+
+    - content_for :"#{id}_body" do
+      .form-group.mb-0{ id: "#{id}_body" }
+        -# Eliminamos las tildes para poder buscar independientemente de cómo se escriba
+        - metadata.values.sort_by(&:remove_diacritics).each do |value|
+          .mb-2{ data: { target: 'array.item', 'searchable-value': value.remove_diacritics.downcase, value: value } }
+            = render 'bootstrap/custom_checkbox', name: name, id: "value-#{Nanoid.generate}", value: value, checked: metadata.value.include?(value), content: value
+
+    - content_for :"#{id}_footer" do
+      .input-group.w-auto.flex-grow-1.my-0
+        %input.form-control{ form: form_id, name: 'value', type: 'text', placeholder: t('.add_new') }
+        .input-group-append
+          = render 'bootstrap/btn', content: t('.add'), form: form_id, type: 'submit', class: 'mb-0 mr-0'
+      = render 'bootstrap/btn', content: t('.accept'), action: 'array#accept modal#hide', class: 'm-0 mr-1'
+      = render 'bootstrap/btn', content: t('.cancel'), action: 'array#cancel modal#hide', class: 'm-0'
+
+    -# Los formularios para HTMX se colocan por fuera del formulario
+       principal, porque HTML5 no soporta formularios anidados. Los campos
+       quedan unidos al formulario por su atributo `id`.
+
+       Al enviar el formulario se obtiene una nueva opción con el valor
+       y se la agrega al final del listado.
+    - content_for :post_form do
+      %form{ id: form_id, 'hx-get': site_posts_new_array_path(site), 'hx-target': "##{id}_body", 'hx-swap': 'beforeend' }
+        %input{ type: 'hidden', name: 'name', value: name }
+        %input{ type: 'hidden', name: 'id', value: form_id }
diff --git a/app/views/posts/new_array.haml b/app/views/posts/new_array.haml
new file mode 100644
index 00000000..62f74854
--- /dev/null
+++ b/app/views/posts/new_array.haml
@@ -0,0 +1,8 @@
+- item_id = "item-#{Nanoid.generate}"
+
+.mb-2{ id: item_id, data: { target: 'array.item', 'searchable-value': @value.remove_diacritics.downcase, value: @value } }
+  .d-flex.flex-row.flex-wrap
+    .flex-grow-1
+      = render 'bootstrap/custom_checkbox', name: @name, id: "value-#{Nanoid.generate}", value: @value, checked: true, content: @value
+    %div
+      %button.btn.btn-sm.m-0{ data: { action: 'array#remove', 'remove-target-param': item_id } }= t('.remove')
diff --git a/app/views/posts/new_array_value.haml b/app/views/posts/new_array_value.haml
new file mode 100644
index 00000000..c71ed3b5
--- /dev/null
+++ b/app/views/posts/new_array_value.haml
@@ -0,0 +1 @@
+= render 'posts/new_array_value', value: @value
diff --git a/config/initializers/core_extensions.rb b/config/initializers/core_extensions.rb
index 7d1eab9e..6861da45 100644
--- a/config/initializers/core_extensions.rb
+++ b/config/initializers/core_extensions.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 String.include CoreExtensions::String::StripTags
+String.include CoreExtensions::String::RemoveDiacritics
 Jekyll::Document.include CoreExtensions::Jekyll::Document::Path
 Jekyll::DataReader.include Jekyll::Readers::DataReaderDecorator
 
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 8fa82473..a7609a40 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -717,7 +717,16 @@ en:
       save_draft: 'Save as draft'
       invalid_help: 'Some fields need attention! Please search for the fields marked as invalid.'
       sending_help: Saving, please wait...
+    new_array:
+      remove: "Remove"
     attributes:
+      new_array:
+        edit: "Edit"
+        filter: "Start typing to filter..."
+        add_new: "Add new option"
+        add: "Add"
+        accept: "Accept"
+        cancel: "Cancel"
       add: Add
       lang:
         label: Language
diff --git a/config/locales/es.yml b/config/locales/es.yml
index 056491ac..1474c935 100644
--- a/config/locales/es.yml
+++ b/config/locales/es.yml
@@ -725,7 +725,16 @@ es:
       save_draft: 'Guardar como borrador'
       invalid_help: '¡Te faltan completar algunos campos! Busca los que estén marcados como inválidos'
       sending_help: Guardando, por favor espera...
+    new_array:
+      remove: "Eliminar"
     attributes:
+      new_array:
+        edit: "Editar"
+        filter: "Empezá a escribir para filtrar..."
+        add_new: "Agregar nueva opción"
+        add: "Agregar"
+        accept: "Aceptar"
+        cancel: "Cancelar"
       add: Agregar
       lang:
         label: Idioma
diff --git a/config/routes.rb b/config/routes.rb
index 9d5c974a..eb20edce 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -99,6 +99,10 @@ Rails.application.routes.draw do
     nested do
       scope '/(:locale)', constraint: /[a-z]{2}(-[A-Z]{2})?/ do
         post :'posts/reorder', to: 'posts#reorder'
+
+        get :'posts/new_array', to: 'posts#new_array'
+        get :'posts/new_array_value', to: 'posts#new_array_value'
+
         resources :posts do
           get 'p/:page', action: :index, on: :collection
           get :preview, to: 'posts#preview'