diff --git a/sources/Forms/Dependency/DependencyException.php b/sources/Forms/Dependency/DependencyException.php
new file mode 100644
index 000000000..60246f3f0
--- /dev/null
+++ b/sources/Forms/Dependency/DependencyException.php
@@ -0,0 +1,12 @@
+<?php
+/*
+ * @copyright   Copyright (C) 2010-2025 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+namespace Combodo\iTop\Forms\Dependency;
+
+class DependencyException extends \Exception
+{
+
+}
\ No newline at end of file
diff --git a/sources/Forms/Dependency/DependencyGraph.php b/sources/Forms/Dependency/DependencyGraph.php
new file mode 100644
index 000000000..6bf1edd04
--- /dev/null
+++ b/sources/Forms/Dependency/DependencyGraph.php
@@ -0,0 +1,78 @@
+<?php
+/*
+ * @copyright   Copyright (C) 2010-2025 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+namespace Combodo\iTop\Forms\Dependency;
+
+class DependencyGraph implements \Iterator
+{
+	use GraphTrait;
+	private array $aFieldNameToPosition = [];
+
+	/**
+	 * @param string $sName
+	 * @param string $sType
+	 * @param array $aDependencies
+	 * @param array $aUserOptions
+	 *
+	 * @return void
+	 * @throws \Combodo\iTop\Forms\Dependency\DependencyException
+	 */
+	public function Add(string $sName, string $sType, array $aDependencies = [], array $aUserOptions = []): void
+	{
+		$oNode = new DependencyNode($sName, $sType, $aUserOptions);
+		// Store field position
+		$this->aFieldNameToPosition[$sName] = count($this->aFieldNameToPosition);
+
+		if (empty($aDependencies)) {
+			$this->AddChild($oNode);
+			return;
+		}
+
+		// Search the last added dependency
+		$oParentNode = null;
+		$iParentPosition = -1;
+		foreach ($aDependencies as $sNodeName) {
+			if ($sNodeName === $sName) {
+				throw new DependencyException("Form field '$sName' cannot reference itself");
+			}
+			if (!isset($this->aFieldNameToPosition[$sNodeName])) {
+				throw new DependencyException("Form field '$sNodeName' is not existing");
+			}
+			if ($this->aFieldNameToPosition[$sNodeName] > $iParentPosition) {
+				$oParentNode = $this->SearchNode($sNodeName);
+				$iParentPosition = $this->aFieldNameToPosition[$sNodeName];
+			}
+		}
+
+		if (is_null($oParentNode)) {
+			throw new DependencyException("Could not find dependency for field '$sName'");
+		}
+
+		// Add to the latest dependency
+		$oParentNode->AddChild($oNode);
+	}
+
+	private function SearchNode(string $sName) : ?DependencyNode
+	{
+		foreach($this as $oChildNode) {
+			$oNode = $oChildNode->SearchNode($sName);
+			if ($oNode instanceof DependencyNode) {
+				return $oNode;
+			}
+		}
+
+		return null;
+	}
+
+	public function __toString(): string
+	{
+		$sResult = "\n";
+		foreach ($this as $oNode) {
+			$sResult .= $oNode->Display();
+		}
+
+		return $sResult;
+	}
+}
\ No newline at end of file
diff --git a/sources/Forms/Dependency/DependencyNode.php b/sources/Forms/Dependency/DependencyNode.php
new file mode 100644
index 000000000..4c7fb0cee
--- /dev/null
+++ b/sources/Forms/Dependency/DependencyNode.php
@@ -0,0 +1,56 @@
+<?php
+/*
+ * @copyright   Copyright (C) 2010-2025 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+namespace Combodo\iTop\Forms\Dependency;
+
+class DependencyNode implements \Iterator
+{
+	use GraphTrait;
+
+	public function __construct(private string $sName, private string $sType, private array $aUserOptions = [])
+	{
+	}
+
+	public function GetType(): string
+	{
+		return $this->sType;
+	}
+
+	public function GetName() : string
+	{
+		return $this->sName;
+	}
+
+	public function GetUserOptions(): array
+	{
+		return $this->aUserOptions;
+	}
+
+	public function SearchNode(string $sName) : ?DependencyNode
+	{
+		if ($sName === $this->GetName()) {
+			return $this;
+		}
+
+		foreach ($this as $oChildNode) {
+			$oNode = $oChildNode->SearchNode($sName);
+			if ($oNode instanceof DependencyNode) {
+				return $oNode;
+			}
+		}
+
+		return null;
+	}
+
+	public function Display(int $iDepth = 1)
+	{
+		$sResult = str_repeat('    ', $iDepth).$this->GetName()."\n";
+		foreach ($this as $oNode) {
+			$sResult .= $oNode->Display($iDepth + 1);
+		}
+
+		return $sResult;
+	}
+}
\ No newline at end of file
diff --git a/sources/Forms/Dependency/GraphTrait.php b/sources/Forms/Dependency/GraphTrait.php
new file mode 100644
index 000000000..fa1aac5e9
--- /dev/null
+++ b/sources/Forms/Dependency/GraphTrait.php
@@ -0,0 +1,50 @@
+<?php
+/*
+ * @copyright   Copyright (C) 2010-2025 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+namespace Combodo\iTop\Forms\Dependency;
+
+trait GraphTrait
+{
+	private array $aChildren = [];
+	private int $iPosition = 0;
+
+	public function AddChild(DependencyNode $node) {
+		$this->aChildren[] = $node;
+	}
+
+	public function IsLast(): bool
+	{
+		return $this->iPosition === count($this->aChildren) - 1;
+	}
+
+	/*
+	 * Iterator interface
+	 */
+	public function current(): mixed
+	{
+		return $this->aChildren[$this->iPosition];
+	}
+
+	public function next(): void
+	{
+		$this->iPosition++;
+	}
+
+	public function key(): mixed
+	{
+		return $this->iPosition;
+	}
+
+	public function valid(): bool
+	{
+		return isset($this->aChildren[$this->iPosition]);
+	}
+
+	public function rewind(): void
+	{
+		$this->iPosition = 0;
+	}
+}
\ No newline at end of file
diff --git a/sources/Forms/FormType/Base/FormBuilder.php b/sources/Forms/FormType/Base/FormBuilder.php
index 1d212c12b..07dad6ea3 100644
--- a/sources/Forms/FormType/Base/FormBuilder.php
+++ b/sources/Forms/FormType/Base/FormBuilder.php
@@ -6,6 +6,7 @@
 
 namespace Combodo\iTop\Forms\FormType\Base;
 
+use Combodo\iTop\Forms\Dependency\DependencyGraph;
 use Combodo\iTop\Forms\FormType\Orm\AttCodeGroupByType;
 use Combodo\iTop\Forms\FormType\Orm\ValuesFromAttcodeType;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
@@ -26,9 +27,12 @@ use Symfony\Component\PropertyAccess\PropertyPathInterface;
 class FormBuilder implements FormBuilderInterface, \IteratorAggregate
 {
 	public array $aModelData = [];
+	private DependencyGraph $oDependencies;
 
 	public function __construct(private FormBuilderInterface $builder)
 	{
+		$this->oDependencies = new DependencyGraph();
+
 		$this->addEventListener(FormEvents::PRE_SUBMIT, function (FormEvent $event) {
 			$this->aModelData = [];
 		});
@@ -36,6 +40,8 @@ class FormBuilder implements FormBuilderInterface, \IteratorAggregate
 
 	public function Finalize(): void
 	{
+		\IssueLog::Info($this->oDependencies);
+
 		$aCallbacks['query'] =  function (FormEvent $event) {
 			if ($event instanceof PostSubmitEvent) {
 				$this->aModelData['query'] = $event->getForm()->getData();
@@ -102,13 +108,10 @@ class FormBuilder implements FormBuilderInterface, \IteratorAggregate
 		$oType = new $type();
 		$aPrerequisites = $oType->GetPrerequisites($options);
 		if (is_null($aPrerequisites)) {
+			$this->oDependencies->Add($child, $type);
 			$this->builder->add($child, $type, $options);
 		} else {
-			$this->aDynamicFields[$child] = [
-				'type' => $type,
-				'prerequisites' => $aPrerequisites,
-				'user_options' => $options,
-			];
+			$this->oDependencies->Add($child, $type, $aPrerequisites, $options);
 			$this->builder->add($child, HiddenType::class, ['mapped' => false]);
 		}
 		return $this;
diff --git a/sources/Forms/FormType/Orm/ValuesFromAttcodeType.php b/sources/Forms/FormType/Orm/ValuesFromAttcodeType.php
index dd59c17f7..f38b70dd8 100644
--- a/sources/Forms/FormType/Orm/ValuesFromAttcodeType.php
+++ b/sources/Forms/FormType/Orm/ValuesFromAttcodeType.php
@@ -55,8 +55,8 @@ class ValuesFromAttcodeType extends AbstractType
 	public function GetPrerequisites(array $aUserOptions): ?array
 	{
 		return [
-			$aUserOptions['source_class'],
 			$aUserOptions['source_attcode'],
+			$aUserOptions['source_class'],
 		];
 	}
 }
\ No newline at end of file