diff --git a/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueFieldName.php b/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueFieldName.php
new file mode 100644
index 0000000000..eddf9d8e3a
--- /dev/null
+++ b/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueFieldName.php
@@ -0,0 +1,135 @@
+<?php
+
+namespace Drupal\migrate\Plugin\migrate\process;
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\migrate\ProcessPluginBase;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\Row;
+use Drupal\migrate\MigrateException;
+use Drupal\migrate\Plugin\MigrationInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * This plugin ensures uniqueness of a field name for a given entity type.
+ *
+ * It also optionally ensures that the field name does not surpass a given
+ * length.
+ *
+ * We can't sub-class MakeUniqueBase for this purpose because while it does
+ * take a length parameter, it only uses it to truncate the input, and does not
+ * guarantee that the output will not exceed that length.
+ *
+ * Available configuration keys:
+ *   - entity_type: The entity type this field might try to be added to.
+ *   - length: (optional) The number of characters to limit to.
+ *
+ * @see \Drupal\migrate\Plugin\MigrateProcessInterface
+ *
+ * @MigrateProcessPlugin(
+ *   id = "make_unique_field_name"
+ * )
+ */
+class MakeUniqueFieldName extends ProcessPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * MakeUniqueFieldName constructor.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin ID.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   *   The entity type manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityTypeManagerInterface $entity_type_manager) {
+    $this->configuration = $configuration;
+    $this->pluginId = $plugin_id;
+    $this->pluginDefinition = $plugin_definition;
+    $this->entityTypeManager = $entity_type_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration = NULL) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity_type.manager')
+    );
+  }
+
+  /**
+   * Creates a unique name for this field for the given entity type.
+   *
+   * @param string $value
+   *   The input string.
+   * @param \Drupal\migrate\MigrateExecutableInterface $migrate_executable
+   *   The migration in which this process is being executed.
+   * @param \Drupal\migrate\Row $row
+   *   The row from the source to process.
+   * @param string $destination_property
+   *   The destination property currently worked on. This is only used together
+   *   with the $row above.
+   *
+   * @return string
+   *   The unique version of the input value.
+   *
+   * @throws \Drupal\migrate\MigrateException
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    $i = 1;
+    $entity_type = isset($this->configuration['entity_type']) ? $this->configuration['entity_type'] : NULL;
+    $length = isset($this->configuration['length']) ? $this->configuration['length'] : NULL;
+    if (!is_null($length) && !is_int($length)) {
+      throw new MigrateException('The character length configuration key should be an integer. Omit this key to allow arbitrary length.');
+    }
+    if (!is_string($entity_type)) {
+      throw new MigrateException('The entity type configuration key is required and should be a string.');
+    }
+    // Start out by trimming the field name to the maximum allowable length.
+    $value = Unicode::substr($value, 0, $length);
+    $new_value = $value;
+    while ($this->exists($new_value, $entity_type)) {
+      // If adding a number to the end to try to obtain uniqueness, ensure we
+      // don't exceed our max length.
+      $new_value = Unicode::substr($value, 0, $length - strlen($i)) . $i;
+      $i++;
+    }
+    return $new_value;
+  }
+
+  /**
+   * Checks if a field name exists on an entity type.
+   *
+   * @param string $field_name
+   *   The field name to check.
+   * @param string $entity_type
+   *   The entity type to check it against.
+   *
+   * @return bool
+   *   TRUE if the field name is already in use on the entity type.
+   */
+  protected function exists($field_name, $entity_type) {
+    $info = $this->entityTypeManager
+      ->getStorage('field_storage_config')
+      ->load($entity_type . '.' . $field_name);
+    if (isset($info)) {
+      return TRUE;
+    }
+    return FALSE;
+  }
+}
diff --git a/core/modules/user/migrations/d6_profile_values.yml b/core/modules/user/migrations/d6_profile_values.yml
index 5530ca5b45..77d979d3c4 100644
--- a/core/modules/user/migrations/d6_profile_values.yml
+++ b/core/modules/user/migrations/d6_profile_values.yml
@@ -5,6 +5,7 @@ migration_tags:
   - Drupal 6
 source:
   plugin: d6_profile_field_values
+  migration: user_profile_field
 process:
   uid: uid
 destination:
diff --git a/core/modules/user/migrations/user_profile_field.yml b/core/modules/user/migrations/user_profile_field.yml
index 3ba0eee48c..4e4a517c01 100644
--- a/core/modules/user/migrations/user_profile_field.yml
+++ b/core/modules/user/migrations/user_profile_field.yml
@@ -9,7 +9,13 @@ source:
     entity_type: user
 process:
   entity_type: 'constants/entity_type'
-  field_name: name
+  field_name:
+    -
+      plugin: machine_name
+      source: name
+    -
+      plugin: make_unique_field_name
+      entity_type: user
   type:
     plugin: static_map
     source: type
diff --git a/core/modules/user/migrations/user_profile_field_instance.yml b/core/modules/user/migrations/user_profile_field_instance.yml
index b9f213b392..bea3f81fce 100644
--- a/core/modules/user/migrations/user_profile_field_instance.yml
+++ b/core/modules/user/migrations/user_profile_field_instance.yml
@@ -13,7 +13,15 @@ process:
   bundle: 'constants/bundle'
   label: title
   description: explanation
-  field_name: name
+  field_name:
+    -
+      plugin: migration_lookup
+      migration: user_profile_field
+      source: fid
+    -
+      plugin: extract
+      index:
+        - 1
   required: required
 destination:
   plugin: entity:field_config
diff --git a/core/modules/user/src/Plugin/migrate/source/d6/ProfileFieldValues.php b/core/modules/user/src/Plugin/migrate/source/d6/ProfileFieldValues.php
index ac4929092d..0502daac89 100644
--- a/core/modules/user/src/Plugin/migrate/source/d6/ProfileFieldValues.php
+++ b/core/modules/user/src/Plugin/migrate/source/d6/ProfileFieldValues.php
@@ -2,18 +2,88 @@
 
 namespace Drupal\user\Plugin\migrate\source\d6;
 
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\State\StateInterface;
+use Drupal\migrate\Plugin\MigrationInterface;
+use Drupal\migrate\Plugin\MigrationPluginManagerInterface;
 use Drupal\migrate\Row;
 use Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
  * Drupal 6 profile fields values source.
  *
+ * Available configuration keys:
+ *   - migration: A single migration ID, or an array of migration IDs.
+ *
+ * Examples:
+ *
+ * This example forces a lookup of profile field names in the migration map
+ * table in case the profile_field migration needed to change the field
+ * name due to a name collision or an field name that contains characters
+ * no longer allowed by Drupal.
+ *
+ * @code
+ * source:
+ *   plugin: d6_profile_field_values
+ *   migration: profile_field
+ * @endcode
+ *
  * @MigrateSource(
  *   id = "d6_profile_field_values",
  *   source_module = "profile"
  * )
  */
-class ProfileFieldValues extends DrupalSqlBase {
+class ProfileFieldValues extends DrupalSqlBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The migration plugin manager.
+   *
+   * @var \Drupal\migrate\Plugin\MigrationPluginManagerInterface
+   */
+  protected $migrationPluginManager;
+
+  /**
+   * Initialize method.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin ID.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\migrate\Plugin\MigrationInterface $migration
+   *   The migration plugin instance.
+   * @param \Drupal\Core\State\StateInterface $state
+   *   The state service.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   * @param \Durpal\migrate\Plugin\MigrationPluginManagerInterface $migration_plugin_manager
+   *   The migration plugin manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration, StateInterface $state, EntityManagerInterface $entity_manager, MigrationPluginManagerInterface $migration_plugin_manager) {
+    $configuration += [
+      'migration' => FALSE,
+    ];
+    parent::__construct($configuration, $plugin_id, $plugin_definition, $migration, $state, $entity_manager);
+    $this->migrationPluginManager = $migration_plugin_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration = NULL) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $migration,
+      $container->get('state'),
+      $container->get('entity.manager'),
+      $container->get('plugin.manager.migration')
+    );
+  }
 
   /**
    * {@inheritdoc}
@@ -39,18 +109,27 @@ public function prepareRow(Row $row) {
     $results = $query->execute();
 
     foreach ($results as $profile_value) {
+      // Find the mapped field name for the profile value.
+      $name = $this->getProfileFieldName($profile_value['fid']);
+      if ($name === FALSE) {
+        $name = $profile_value['name'];
+      }
+
       // Check special case for date. We need to unserialize.
       if ($profile_value['type'] == 'date') {
         $date = unserialize($profile_value['value']);
         $date = date('Y-m-d', mktime(0, 0, 0, $date['month'], $date['day'], $date['year']));
-        $row->setSourceProperty($profile_value['name'], ['value' => $date]);
+        $row->setSourceProperty($name, ['value' => $date]);
+        $row->setDestinationProperty($name, ['value' => $date]);
       }
       elseif ($profile_value['type'] == 'list') {
         // Explode by newline and comma.
-        $row->setSourceProperty($profile_value['name'], preg_split("/[\r\n,]+/", $profile_value['value']));
+        $row->setSourceProperty($name, preg_split("/[\r\n,]+/", $profile_value['value']));
+        $row->setDestinationProperty($name, preg_split("/[\r\n,]+/", $profile_value['value']));
       }
       else {
-        $row->setSourceProperty($profile_value['name'], [$profile_value['value']]);
+        $row->setSourceProperty($name, [$profile_value['value']]);
+        $row->setDestinationProperty($name, [$profile_value['value']]);
       }
     }
 
@@ -91,4 +170,42 @@ public function getIds() {
     ];
   }
 
+  /**
+   * Lookup the profile field name based on migration.
+   *
+   * @param string $sourceName
+   *   The raw profile field name from the source data.
+   *
+   * @return string
+   *   The mapped profile field name
+   */
+  protected function getProfileFieldName($sourceID) {
+    $migration_ids = $this->configuration['migration'];
+    if (!is_array($migration_ids)) {
+      $migration_ids = [$migration_ids];
+    }
+    $sourceValues = [$sourceID];
+    /** @var \Drupal\migrate\Plugin\MigrationInterface[] $migrations */
+    $migrations = $this->migrationPluginManager->createInstances($migration_ids);
+    $destination_ids = NULL;
+    foreach ($migrations as $migration_id => $migration) {
+      if ($destination_ids = $migration->getIdMap()->lookupDestinationId($sourceValues)) {
+        break;
+      }
+    }
+
+    if (!$destination_ids) {
+      // Nothing found.
+      return FALSE;
+    }
+    elseif (count($destination_ids) === 2) {
+      // Destination IDs for fields are an array of the entity type and field
+      // name in that order.
+      return $destination_ids[1];
+    }
+
+    // Return the first found destination ID.
+    return reset($destination_ids);
+  }
+
 }