diff --git a/src/ORM/ArrayLib.php b/src/ORM/ArrayLib.php
index 371d0f6dfca..d3c4815e6f1 100644
--- a/src/ORM/ArrayLib.php
+++ b/src/ORM/ArrayLib.php
@@ -3,12 +3,20 @@
 namespace SilverStripe\ORM;
 
 use Generator;
+use SilverStripe\Dev\Deprecation;
 
 /**
  * Library of static methods for manipulating arrays.
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib
  */
 class ArrayLib
 {
+    public function __construct()
+    {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib', Deprecation::SCOPE_CLASS);
+        });
+    }
 
     /**
      * Inverses the first and second level keys of an associative
@@ -45,9 +53,14 @@ class ArrayLib
      *
      * @param array $arr
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::invert()
      */
     public static function invert($arr)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::invert()');
+        });
+
         if (!$arr) {
             return [];
         }
@@ -68,9 +81,14 @@ public static function invert($arr)
      *
      * @param $arr array
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::valuekey()
      */
     public static function valuekey($arr)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::valuekey()');
+        });
+
         return array_combine($arr ?? [], $arr ?? []);
     }
 
@@ -79,9 +97,14 @@ public static function valuekey($arr)
      *
      * @param array $array
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::array_values_recursive()
      */
     public static function array_values_recursive($array)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::invearray_values_recursivert()');
+        });
+
         return ArrayLib::flatten($array, false);
     }
 
@@ -93,9 +116,14 @@ public static function array_values_recursive($array)
      * @param $keys array
      *
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::filter_keys()
      */
     public static function filter_keys($arr, $keys)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::filter_keys()');
+        });
+
         foreach ($arr as $key => $v) {
             if (!in_array($key, $keys ?? [])) {
                 unset($arr[$key]);
@@ -114,9 +142,14 @@ public static function filter_keys($arr, $keys)
      * @param array $array
      *
      * @return boolean
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::is_associative()
      */
     public static function is_associative($array)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::is_associative()');
+        });
+
         $isAssociative = !empty($array)
             && is_array($array)
             && ($array !== array_values($array ?? []));
@@ -135,9 +168,14 @@ public static function is_associative($array)
      * @param boolean $strict
      *
      * @return boolean
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::in_array_recursive()
      */
     public static function in_array_recursive($needle, $haystack, $strict = false)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::in_array_recursive()');
+        });
+
         if (!is_array($haystack)) {
             return false;
         }
@@ -163,9 +201,14 @@ public static function in_array_recursive($needle, $haystack, $strict = false)
      * @param $f callback to apply
      * @param $array array
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::array_map_recursive()
      */
     public static function array_map_recursive($f, $array)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::array_map_recursive()');
+        });
+
         $applyOrRecurse = function ($v) use ($f) {
             return is_array($v) ? ArrayLib::array_map_recursive($f, $v) : call_user_func($f, $v);
         };
@@ -184,9 +227,14 @@ public static function array_map_recursive($f, $array)
      * @param array $array
      *
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::array_merge_recursive()
      */
     public static function array_merge_recursive($array)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::array_merge_recursive()');
+        });
+
         $arrays = func_get_args();
         $merged = [];
 
@@ -229,9 +277,14 @@ public static function array_merge_recursive($array)
      * @param array $out
      *
      * @return array
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::flatten()
      */
     public static function flatten($array, $preserveKeys = true, &$out = [])
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::flatten()');
+        });
+
         array_walk_recursive(
             $array,
             function ($value, $key) use (&$out, $preserveKeys) {
@@ -256,9 +309,14 @@ function ($value, $key) use (&$out, $preserveKeys) {
      *
      * @param array $list
      * @return Generator
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::iterateVolatile()
      */
     public static function iterateVolatile(array &$list)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::iterateVolatile()');
+        });
+
         // Keyed by already-iterated items
         $iterated = [];
         // Get all items not yet iterated
@@ -278,9 +336,14 @@ public static function iterateVolatile(array &$list)
     /**
      * Similar to shuffle, but retains the existing association between the keys and the values.
      * Shuffles the array in place.
+     * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\ArrayLib::shuffleAssociative()
      */
     public static function shuffleAssociative(array &$array): void
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\ArrayLib::shuffleAssociative()');
+        });
+
         $shuffledArray = [];
         $keys = array_keys($array);
         shuffle($keys);
diff --git a/src/ORM/ArrayList.php b/src/ORM/ArrayList.php
index 16fc11de402..94920fe3e99 100644
--- a/src/ORM/ArrayList.php
+++ b/src/ORM/ArrayList.php
@@ -35,6 +35,7 @@
  * @implements Filterable<T>
  * @implements Sortable<T>
  * @implements Limitable<T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\ArrayList
  */
 class ArrayList extends ViewableData implements SS_List, Filterable, Sortable, Limitable
 {
@@ -60,6 +61,10 @@ class ArrayList extends ViewableData implements SS_List, Filterable, Sortable, L
      */
     public function __construct(array $items = [])
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\List\ArrayList', Deprecation::SCOPE_CLASS);
+        });
+
         $this->items = array_values($items ?? []);
         parent::__construct();
     }
diff --git a/src/ORM/Filterable.php b/src/ORM/Filterable.php
index ce5196e4654..4caf7032fc7 100644
--- a/src/ORM/Filterable.php
+++ b/src/ORM/Filterable.php
@@ -14,6 +14,7 @@
  *
  * @template T
  * @extends SS_List<T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\Filterable
  */
 interface Filterable extends SS_List
 {
diff --git a/src/ORM/GroupedList.php b/src/ORM/GroupedList.php
index 6fdd257d80d..e81d5bbbede 100644
--- a/src/ORM/GroupedList.php
+++ b/src/ORM/GroupedList.php
@@ -2,6 +2,7 @@
 
 namespace SilverStripe\ORM;
 
+use SilverStripe\Dev\Deprecation;
 use SilverStripe\View\ArrayData;
 
 /**
@@ -11,10 +12,19 @@
  * @template TList
  * @template T
  * @extends ListDecorator<TList, T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\GroupedList
  */
 class GroupedList extends ListDecorator
 {
 
+    public function __construct(SS_List&Sortable&Filterable&Limitable $list)
+    {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\List\GroupedList', Deprecation::SCOPE_CLASS);
+        });
+        parent::__construct($list);
+    }
+
     /**
      * @param  string $index
      * @return array
diff --git a/src/ORM/Limitable.php b/src/ORM/Limitable.php
index 4a2d37b3ad0..f9e29064943 100644
--- a/src/ORM/Limitable.php
+++ b/src/ORM/Limitable.php
@@ -14,6 +14,7 @@
  *
  * @template T
  * @implements SS_List<T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\Limitable
  */
 interface Limitable extends SS_List
 {
diff --git a/src/ORM/ListDecorator.php b/src/ORM/ListDecorator.php
index b063acb7481..94712368afe 100644
--- a/src/ORM/ListDecorator.php
+++ b/src/ORM/ListDecorator.php
@@ -4,6 +4,7 @@
 
 use SilverStripe\View\ViewableData;
 use LogicException;
+use SilverStripe\Dev\Deprecation;
 use Traversable;
 
 /**
@@ -17,6 +18,7 @@
  * @implements Sortable<T>
  * @implements Filterable<T>
  * @implements Limitable<T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\ListDecorator
  */
 abstract class ListDecorator extends ViewableData implements SS_List, Sortable, Filterable, Limitable
 {
@@ -30,6 +32,10 @@ abstract class ListDecorator extends ViewableData implements SS_List, Sortable,
      */
     public function __construct(SS_List&Sortable&Filterable&Limitable $list)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\List\ListDecorator', Deprecation::SCOPE_CLASS);
+        });
+
         $this->setList($list);
 
         parent::__construct();
diff --git a/src/ORM/Map.php b/src/ORM/Map.php
index a1b81f609d8..186cf2246fd 100644
--- a/src/ORM/Map.php
+++ b/src/ORM/Map.php
@@ -6,10 +6,13 @@
 use BadMethodCallException;
 use Countable;
 use IteratorAggregate;
+use SilverStripe\Dev\Deprecation;
 use Traversable;
 
 /**
  * Creates a map from an SS_List by defining a key column and a value column.
+ *
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\Map
  */
 class Map implements ArrayAccess, Countable, IteratorAggregate
 {
@@ -39,6 +42,10 @@ class Map implements ArrayAccess, Countable, IteratorAggregate
      */
     public function __construct(SS_List $list, $keyField = "ID", $valueField = "Title")
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\List\Map', Deprecation::SCOPE_CLASS);
+        });
+
         $this->list = $list;
         $this->keyField = $keyField;
         $this->valueField = $valueField;
diff --git a/src/ORM/PaginatedList.php b/src/ORM/PaginatedList.php
index 99e7ebb818a..b7d392700f4 100644
--- a/src/ORM/PaginatedList.php
+++ b/src/ORM/PaginatedList.php
@@ -9,6 +9,7 @@
 use ArrayAccess;
 use Exception;
 use IteratorIterator;
+use SilverStripe\Dev\Deprecation;
 use Traversable;
 
 /**
@@ -17,6 +18,7 @@
  * @template TList of SS_List
  * @template T
  * @extends ListDecorator<TList, T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\PaginatedList
  */
 class PaginatedList extends ListDecorator
 {
@@ -39,6 +41,10 @@ class PaginatedList extends ListDecorator
      */
     public function __construct(SS_List $list, $request = [])
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\List\PaginatedList', Deprecation::SCOPE_CLASS);
+        });
+
         if (!is_array($request) && !$request instanceof ArrayAccess) {
             throw new Exception('The request must be readable as an array.');
         }
diff --git a/src/ORM/SS_List.php b/src/ORM/SS_List.php
index 2aa82783d3f..4cb769a86ba 100644
--- a/src/ORM/SS_List.php
+++ b/src/ORM/SS_List.php
@@ -12,6 +12,8 @@
  * @template T
  * @extends ArrayAccess<array-key, T>
  * @extends IteratorAggregate<array-key, T>
+ *
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\SS_List
  */
 interface SS_List extends ArrayAccess, Countable, IteratorAggregate
 {
diff --git a/src/ORM/Sortable.php b/src/ORM/Sortable.php
index 07c9e92fc5a..2fd84c9111c 100644
--- a/src/ORM/Sortable.php
+++ b/src/ORM/Sortable.php
@@ -14,6 +14,7 @@
  *
  * @template T
  * @implements SS_List<T>
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\List\Sortable
  */
 interface Sortable extends SS_List
 {
diff --git a/src/ORM/ValidationException.php b/src/ORM/ValidationException.php
index 88f9192094b..1ee47db2793 100644
--- a/src/ORM/ValidationException.php
+++ b/src/ORM/ValidationException.php
@@ -5,11 +5,14 @@
 use Exception;
 use InvalidArgumentException;
 use SilverStripe\Core\Injector\Injectable;
+use SilverStripe\Dev\Deprecation;
 
 /**
  * Exception thrown by {@link DataObject}::write if validation fails. By throwing an
  * exception rather than a user error, the exception can be caught in unit tests and as such
  * can be used as a successful test.
+ *
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\Validation\ValidationException
  */
 class ValidationException extends Exception
 {
@@ -31,6 +34,10 @@ class ValidationException extends Exception
      */
     public function __construct($result = null, $code = 0)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\Validation\ValidationException', Deprecation::SCOPE_CLASS);
+        });
+
         // Catch legacy behaviour where second argument was not code
         if ($code && !is_numeric($code)) {
             throw new InvalidArgumentException("Code must be numeric");
diff --git a/src/ORM/ValidationResult.php b/src/ORM/ValidationResult.php
index 8ba3ba545ba..d57a3b8b24d 100644
--- a/src/ORM/ValidationResult.php
+++ b/src/ORM/ValidationResult.php
@@ -4,6 +4,7 @@
 
 use InvalidArgumentException;
 use SilverStripe\Core\Injector\Injectable;
+use SilverStripe\Dev\Deprecation;
 
 /**
  * A class that combined as a boolean result with an optional list of error messages.
@@ -11,6 +12,8 @@
  *
  * Each message can have a code or field which will uniquely identify that message. However,
  * messages can be stored without a field or message as an "overall" message.
+ *
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Core\Validation\ValidationResult
  */
 class ValidationResult
 {
@@ -61,6 +64,13 @@ class ValidationResult
      */
     protected $messages = [];
 
+    public function __construct()
+    {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Core\Validation\ValidationResult', Deprecation::SCOPE_CLASS);
+        });
+    }
+
     /**
      * Record an error against this validation result,
      *
diff --git a/src/View/ArrayData.php b/src/View/ArrayData.php
index 1d166de5305..34786a962b1 100644
--- a/src/View/ArrayData.php
+++ b/src/View/ArrayData.php
@@ -4,6 +4,7 @@
 
 use SilverStripe\ORM\ArrayLib;
 use InvalidArgumentException;
+use SilverStripe\Dev\Deprecation;
 use stdClass;
 
 /**
@@ -15,6 +16,8 @@
  *    "AddAction" => "Add a new Page page",
  * ));
  * </code>
+ *
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\ArrayData
  */
 class ArrayData extends ViewableData
 {
@@ -31,6 +34,10 @@ class ArrayData extends ViewableData
      */
     public function __construct($value = [])
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\ArrayData', Deprecation::SCOPE_CLASS);
+        });
+
         if (is_object($value)) {
             $this->array = get_object_vars($value);
         } elseif (is_array($value)) {
diff --git a/src/View/ViewableData.php b/src/View/ViewableData.php
index d729d36da72..37970ba691d 100644
--- a/src/View/ViewableData.php
+++ b/src/View/ViewableData.php
@@ -32,6 +32,8 @@
  * A view interrogates the object being currently rendered in order to get data to render into the template. This data
  * is provided and automatically escaped by ViewableData. Any class that needs to be available to a view (controllers,
  * {@link DataObject}s, page controls) should inherit from this class.
+ *
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\ModelData
  */
 class ViewableData implements IteratorAggregate
 {
@@ -97,6 +99,9 @@ class ViewableData implements IteratorAggregate
 
     public function __construct()
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\ModelData', Deprecation::SCOPE_CLASS);
+        });
     }
 
     // -----------------------------------------------------------------------------------------------------------------
diff --git a/src/View/ViewableData_Customised.php b/src/View/ViewableData_Customised.php
index a8589bb51a8..0988b2957f7 100644
--- a/src/View/ViewableData_Customised.php
+++ b/src/View/ViewableData_Customised.php
@@ -2,6 +2,11 @@
 
 namespace SilverStripe\View;
 
+use SilverStripe\Dev\Deprecation;
+
+/**
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\ModelDataCustomised
+ */
 class ViewableData_Customised extends ViewableData
 {
 
@@ -18,6 +23,10 @@ class ViewableData_Customised extends ViewableData
      */
     public function __construct(ViewableData $originalObject, ViewableData $customisedObject)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\ModelDataCustomised', Deprecation::SCOPE_CLASS);
+        });
+
         $this->original = $originalObject;
         $this->customised = $customisedObject;
 
diff --git a/src/View/ViewableData_Debugger.php b/src/View/ViewableData_Debugger.php
index 9c496c99a4f..c2ea7357b6c 100644
--- a/src/View/ViewableData_Debugger.php
+++ b/src/View/ViewableData_Debugger.php
@@ -3,9 +3,11 @@
 namespace SilverStripe\View;
 
 use ReflectionObject;
+use SilverStripe\Dev\Deprecation;
 
 /**
  * Allows you to render debug information about a {@link ViewableData} object into a template.
+ * @deprecated 5.4.0 Will be renamed to SilverStripe\Model\ModelDataDebugger
  */
 class ViewableData_Debugger extends ViewableData
 {
@@ -20,6 +22,9 @@ class ViewableData_Debugger extends ViewableData
      */
     public function __construct(ViewableData $object)
     {
+        Deprecation::withNoReplacement(function () {
+            Deprecation::notice('5.4.0', 'Will be renamed to SilverStripe\Model\ModelDataDebugger', Deprecation::SCOPE_CLASS);
+        });
         $this->object = $object;
         parent::__construct();
     }