diff --git a/.gitignore b/.gitignore
index 21799d6..752f38c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,7 +2,8 @@
 !*/
 !/.gitignore
 !/scripts/**
+!/web/modules/custom/**
 !/web/sites/default/environments/settings.*.php
 !/web/sites/default/settings.php
 !/web/themes/custom/**
-/web/themes/custom/*/dist/
\ No newline at end of file
+/web/themes/custom/*/dist/
diff --git a/web/modules/custom/custom/custom.info.yml b/web/modules/custom/custom/custom.info.yml
new file mode 100644
index 0000000..82617ad
--- /dev/null
+++ b/web/modules/custom/custom/custom.info.yml
@@ -0,0 +1,5 @@
+name: Oliver Davies custom module
+type: module
+core: 8.x
+core_version_requirements: ^8 || ^9
+package: Custom
diff --git a/web/modules/custom/custom/drush.services.yml b/web/modules/custom/custom/drush.services.yml
new file mode 100644
index 0000000..ffa0410
--- /dev/null
+++ b/web/modules/custom/custom/drush.services.yml
@@ -0,0 +1,5 @@
+services:
+  Drupal\custom\Command\FormatTagNamesCommand:
+    autowire: true
+    tags:
+      - { name: drush.command }
diff --git a/web/modules/custom/custom/src/Command/FormatTagNamesCommand.php b/web/modules/custom/custom/src/Command/FormatTagNamesCommand.php
new file mode 100644
index 0000000..ef43808
--- /dev/null
+++ b/web/modules/custom/custom/src/Command/FormatTagNamesCommand.php
@@ -0,0 +1,136 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\custom\Command;
+
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drush\Commands\DrushCommands;
+
+final class FormatTagNamesCommand extends DrushCommands {
+
+  /**
+   * The taxonomy term storage.
+   *
+   * @var \Drupal\Core\Entity\EntityStorageInterface
+   */
+  private $termStorage;
+
+  /**
+   * A lookup table for new name overrides.
+   *
+   * @var array
+   *   An associative array, keyed by the original tag name. The value is either
+   *   an overridden tag name or FALSE if the tag name is not to be changed.
+   */
+  static $tagNames = [
+    'accessible-bristol' => 'Accessible Bristol',
+    'admin:hover' => FALSE,
+    'aria' => 'ARIA',
+    'cck' => 'CCK',
+    'centos' => 'CentOS',
+    'css' => 'CSS',
+    'dcbristol' => FALSE,
+    'ddev' => 'DDEV',
+    'drupal-association' => 'Drupal Association',
+    'drupal-bristol' => 'Drupal Bristol',
+    'drupal-commerce' => 'Drupal Commerce',
+    'drupal-planet' => 'Drupal Planet',
+    'drupal-vm' => 'Drupal VM',
+    'drupal-vm-generator' => 'Drupal VM Generator',
+    'drupalcamp' => 'DrupalCamp',
+    'drupalcamp-bristol' => 'DrupalCamp Bristol',
+    'drupalcamp-london' => 'DrupalCamp London',
+    'drupalcamp-north' => 'DrupalCamp North',
+    'drupalcon' => 'DrupalCon',
+    'entity-api' => 'Entity API',
+    'fancy-slide' => 'Fancy Slide',
+    'field-collection' => 'Field Collection',
+    'filefield' => 'FileField',
+    'form-api' => 'Form API',
+    'git-flow' => 'Git Flow',
+    'github' => 'GitHub',
+    'illuminate-collections' => 'Illuminate Collections',
+    'image-caption' => 'Image Caption',
+    'imagecache' => 'ImageCache',
+    'imagefield' => 'ImageField',
+    'imagefield-import' => 'ImageField Import',
+    'javascript' => 'JavaScript',
+    'laravel-collections' => 'Laravel Collections',
+    'laravel-mix' => 'Laravel Mix',
+    'linux-journal' => 'Linux Journal',
+    'mac-os-x' => 'macOS',
+    'mamp' => 'MAMP',
+    'mod_rewrite' => FALSE,
+    'npm' => FALSE,
+    'oliverdavies.co.uk' => FALSE,
+    'php' => 'PHP',
+    'php-south-wales' => 'PHP South Wales',
+    'phpstorm' => 'PhpStorm',
+    'phpsw' => 'PHPSW',
+    'phpunit' => 'PHPUnit',
+    'postcss' => 'PostCSS',
+    'psr' => 'PSR',
+    'regular-expression' => 'Regular expressions',
+    'sequel-pro' => 'Sequel Pro',
+    'settings.php' => FALSE,
+    'sql' => 'SQL',
+    'ssh' => 'SSH',
+    'sublime-text' => 'Sublime Text',
+    'svn' => 'SVN',
+    'swdug' => 'SWDUG',
+    'symfonylive' => 'SymfonyLive',
+    'tailwind-css' => 'Tailwind CSS',
+    'tdd' => 'TDD',
+    'views-attach' => 'Views Attach',
+    'virtualbox' => 'VirtualBox',
+    'vuejs' => 'VueJS',
+    'virtualhostx' => 'VirtualHostX',
+  ];
+
+  public function __construct(EntityTypeManagerInterface $entityTypeManager) {
+    parent::__construct();
+
+    $this->termStorage = $entityTypeManager->getStorage('taxonomy_term');
+  }
+
+  /**
+   * Drush command for updating legacy tag names.
+   *
+   * @command opdavies:update-tag-names
+   */
+  public function updateTagNames(): void {
+    foreach ($this->getTags() as $tag) {
+      $name = $tag->label();
+      $newName = $this->getNewTagName($name);
+
+      if ($newName === NULL) {
+        $this->writeln(sprintf('Skipping %s.', $name));
+        continue;
+      }
+
+      $this->writeln(sprintf('Updating %s to %s.', $name, $newName));
+      $tag->name = $newName;
+      $tag->save();
+    }
+  }
+
+  private function getTags(): array {
+    return $this->termStorage->loadByProperties([
+      'vid' => 'tags',
+    ]);
+  }
+
+  private function getNewTagName(string $tagName): ?string {
+    if (!array_key_exists($tagName, static::$tagNames)) {
+      return str_replace('-', ' ', ucfirst($tagName));
+    }
+
+    if (static::$tagNames[$tagName] === FALSE) {
+      return NULL;
+    }
+
+    return static::$tagNames[$tagName];
+  }
+
+}