diff --git a/application/forms/AddNodeForm.php b/application/forms/AddNodeForm.php
index 43afa4c..5ef11c7 100644
--- a/application/forms/AddNodeForm.php
+++ b/application/forms/AddNodeForm.php
@@ -7,6 +7,7 @@ use Icinga\Module\Businessprocess\BpConfig;
 use Icinga\Module\Businessprocess\Common\EnumList;
 use Icinga\Module\Businessprocess\ImportedNode;
 use Icinga\Module\Businessprocess\Modification\ProcessChanges;
+use Icinga\Module\Businessprocess\Node;
 use Icinga\Module\Businessprocess\Storage\Storage;
 use Icinga\Module\Businessprocess\Web\Form\QuickForm;
 use Icinga\Module\Businessprocess\Web\Form\Validator\NoDuplicateChildrenValidator;
@@ -113,21 +114,7 @@ class AddNodeForm extends QuickForm
         $this->addElement('select', 'operator', array(
             'label'        => $this->translate('Operator'),
             'required'     => true,
-            'multiOptions' => array(
-                '&' => $this->translate('AND'),
-                '|' => $this->translate('OR'),
-                '!' => $this->translate('NOT'),
-                '%' => $this->translate('DEGRADED'),
-                '1' => $this->translate('MIN 1'),
-                '2' => $this->translate('MIN 2'),
-                '3' => $this->translate('MIN 3'),
-                '4' => $this->translate('MIN 4'),
-                '5' => $this->translate('MIN 5'),
-                '6' => $this->translate('MIN 6'),
-                '7' => $this->translate('MIN 7'),
-                '8' => $this->translate('MIN 8'),
-                '9' => $this->translate('MIN 9'),
-            )
+            'multiOptions' => Node::getOperators()
         ));
 
         $display = 1;
diff --git a/application/forms/EditNodeForm.php b/application/forms/EditNodeForm.php
index eceb065..f26dd04 100644
--- a/application/forms/EditNodeForm.php
+++ b/application/forms/EditNodeForm.php
@@ -111,21 +111,7 @@ class EditNodeForm extends QuickForm
         $this->addElement('select', 'operator', array(
             'label'        => $this->translate('Operator'),
             'required'     => true,
-            'multiOptions' => array(
-                '&' => $this->translate('AND'),
-                '|' => $this->translate('OR'),
-                '!' => $this->translate('NOT'),
-                '%' => $this->translate('DEGRADED'),
-                '1' => $this->translate('MIN 1'),
-                '2' => $this->translate('MIN 2'),
-                '3' => $this->translate('MIN 3'),
-                '4' => $this->translate('MIN 4'),
-                '5' => $this->translate('MIN 5'),
-                '6' => $this->translate('MIN 6'),
-                '7' => $this->translate('MIN 7'),
-                '8' => $this->translate('MIN 8'),
-                '9' => $this->translate('MIN 9'),
-            )
+            'multiOptions' => Node::getOperators()
         ));
 
         $display = $this->getNode()->getDisplay() ?: 1;
diff --git a/application/forms/ProcessForm.php b/application/forms/ProcessForm.php
index be1abbf..604b774 100644
--- a/application/forms/ProcessForm.php
+++ b/application/forms/ProcessForm.php
@@ -5,6 +5,7 @@ namespace Icinga\Module\Businessprocess\Forms;
 use Icinga\Module\Businessprocess\BpNode;
 use Icinga\Module\Businessprocess\BpConfig;
 use Icinga\Module\Businessprocess\Modification\ProcessChanges;
+use Icinga\Module\Businessprocess\Node;
 use Icinga\Module\Businessprocess\Web\Form\QuickForm;
 use Icinga\Module\Monitoring\Backend\MonitoringBackend;
 use Icinga\Web\Notification;
@@ -58,21 +59,7 @@ class ProcessForm extends QuickForm
         $this->addElement('select', 'operator', array(
             'label'        => $this->translate('Operator'),
             'required'     => true,
-            'multiOptions' => array(
-                '&' => $this->translate('AND'),
-                '|' => $this->translate('OR'),
-                '!' => $this->translate('NOT'),
-                '%' => $this->translate('DEGRADED'),
-                '1' => $this->translate('MIN 1'),
-                '2' => $this->translate('MIN 2'),
-                '3' => $this->translate('MIN 3'),
-                '4' => $this->translate('MIN 4'),
-                '5' => $this->translate('MIN 5'),
-                '6' => $this->translate('MIN 6'),
-                '7' => $this->translate('MIN 7'),
-                '8' => $this->translate('MIN 8'),
-                '9' => $this->translate('MIN 9'),
-            )
+            'multiOptions' => Node::getOperators()
         ));
 
         if ($this->node !== null) {
diff --git a/doc/09-Operators.md b/doc/09-Operators.md
index 58db97c..ba2f51d 100644
--- a/doc/09-Operators.md
+++ b/doc/09-Operators.md
@@ -17,6 +17,16 @@ The `OR` operator selects the **BEST** state of its child nodes:
 
 ![Or Operator #2](screenshot/09_operators/0903_or-operator-without-ok.png)
 
+## XOR <a id="xor-operator">
+
+The `XOR` operator shows OK if only one of n children is OK at the same time. In all other cases the parent node is CRITICAL.
+Useful for a service on n servers, only one of which may be running. If both were running,
+race conditions and duplication of data could occur.
+
+![Xor Operator](screenshot/09_operators/0906_xor-operator.png)
+
+![Xor Operator #2](screenshot/09_operators/0907_xor-operator-not-ok.png)
+
 ## DEGRADED <a id="deg-operator">
 
 The `DEGRADED` operator behaves like an `AND`, but if the resulting
diff --git a/doc/screenshot/09_operators/0901_and-operator.png b/doc/screenshot/09_operators/0901_and-operator.png
index a939843..c6e7775 100644
Binary files a/doc/screenshot/09_operators/0901_and-operator.png and b/doc/screenshot/09_operators/0901_and-operator.png differ
diff --git a/doc/screenshot/09_operators/0902_or-operator.png b/doc/screenshot/09_operators/0902_or-operator.png
index ff6dafa..fd05ec3 100644
Binary files a/doc/screenshot/09_operators/0902_or-operator.png and b/doc/screenshot/09_operators/0902_or-operator.png differ
diff --git a/doc/screenshot/09_operators/0903_or-operator-without-ok.png b/doc/screenshot/09_operators/0903_or-operator-without-ok.png
index b8097ee..e9fcd4e 100644
Binary files a/doc/screenshot/09_operators/0903_or-operator-without-ok.png and b/doc/screenshot/09_operators/0903_or-operator-without-ok.png differ
diff --git a/doc/screenshot/09_operators/0904_min-operator.png b/doc/screenshot/09_operators/0904_min-operator.png
index 04fa9be..fd05ec3 100644
Binary files a/doc/screenshot/09_operators/0904_min-operator.png and b/doc/screenshot/09_operators/0904_min-operator.png differ
diff --git a/doc/screenshot/09_operators/0906_xor-operator.png b/doc/screenshot/09_operators/0906_xor-operator.png
new file mode 100644
index 0000000..fd05ec3
Binary files /dev/null and b/doc/screenshot/09_operators/0906_xor-operator.png differ
diff --git a/doc/screenshot/09_operators/0907_xor-operator-not-ok.png b/doc/screenshot/09_operators/0907_xor-operator-not-ok.png
new file mode 100644
index 0000000..8ec41b3
Binary files /dev/null and b/doc/screenshot/09_operators/0907_xor-operator-not-ok.png differ
diff --git a/library/Businessprocess/BpNode.php b/library/Businessprocess/BpNode.php
index a61c984..10e3655 100644
--- a/library/Businessprocess/BpNode.php
+++ b/library/Businessprocess/BpNode.php
@@ -10,6 +10,7 @@ class BpNode extends Node
 {
     const OP_AND = '&';
     const OP_OR  = '|';
+    const OP_XOR  = '^';
     const OP_NOT  = '!';
     const OP_DEGRADED  = '%';
 
@@ -303,6 +304,7 @@ class BpNode extends Node
         switch ($operator) {
             case self::OP_AND:
             case self::OP_OR:
+            case self::OP_XOR:
             case self::OP_NOT:
             case self::OP_DEGRADED:
                 return;
@@ -476,6 +478,21 @@ class BpNode extends Node
             case self::OP_OR:
                 $sort_state = min($sort_states);
                 break;
+            case self::OP_XOR:
+                $actualGood = 0;
+                foreach ($sort_states as $s) {
+                    if ($this->sortStateTostate($s) === self::ICINGA_OK) {
+                        $actualGood++;
+                    }
+                }
+
+                if ($actualGood === 1) {
+                    $this->state = self::ICINGA_OK;
+                } else {
+                    $this->state = self::ICINGA_CRITICAL;
+                }
+
+                return $this;
             case self::OP_DEGRADED:
                 $maxState = max($sort_states);
                 $flags = $maxState & 0xf;
@@ -645,6 +662,8 @@ class BpNode extends Node
                 break;
             case self::OP_OR:
                 return 'OR';
+            case self::OP_XOR:
+                return 'XOR';
                 break;
             case self::OP_NOT:
                 return 'NOT';
diff --git a/library/Businessprocess/Node.php b/library/Businessprocess/Node.php
index a9eb44c..73236ce 100644
--- a/library/Businessprocess/Node.php
+++ b/library/Businessprocess/Node.php
@@ -483,6 +483,31 @@ abstract class Node
         return $this->name;
     }
 
+    /**
+     * Get the Node operators
+     *
+     * @return array
+     */
+    public static function getOperators(): array
+    {
+        return [
+            '&' => t('AND'),
+            '|' => t('OR'),
+            '^' => t('XOR'),
+            '!' => t('NOT'),
+            '%' => t('DEGRADED'),
+            '1' => t('MIN 1'),
+            '2' => t('MIN 2'),
+            '3' => t('MIN 3'),
+            '4' => t('MIN 4'),
+            '5' => t('MIN 5'),
+            '6' => t('MIN 6'),
+            '7' => t('MIN 7'),
+            '8' => t('MIN 8'),
+            '9' => t('MIN 9'),
+        ];
+    }
+
     public function getIdentifier()
     {
         return '@' . $this->getBpConfig()->getName() . ':' . $this->getName();
diff --git a/library/Businessprocess/Storage/LegacyConfigParser.php b/library/Businessprocess/Storage/LegacyConfigParser.php
index 834e56d..437e369 100644
--- a/library/Businessprocess/Storage/LegacyConfigParser.php
+++ b/library/Businessprocess/Storage/LegacyConfigParser.php
@@ -349,7 +349,7 @@ class LegacyConfigParser
         }
 
         $op = '&';
-        if (preg_match_all('~(?<!\\\\)([\|\+&\!\%])~', $value, $m)) {
+        if (preg_match_all('~(?<!\\\\)([\|\+&\!\%\^])~', $value, $m)) {
             $op = implode('', $m[1]);
             for ($i = 1; $i < strlen($op); $i++) {
                 if ($op[$i] !== $op[$i - 1]) {
@@ -378,7 +378,7 @@ class LegacyConfigParser
 
         $cmps = preg_split('~\s*(?<!\\\\)\\' . $op . '\s*~', $value, -1, PREG_SPLIT_NO_EMPTY);
         foreach ($cmps as $val) {
-            $val = preg_replace('~(\\\\([\|\+&\!\%]))~', '$2', $val);
+            $val = preg_replace('~(\\\\([\|\+&\!\%\^]))~', '$2', $val);
             if (strpos($val, ';') !== false) {
                 if ($bp->hasNode($val)) {
                     $node->addChild($bp->getNode($val));
diff --git a/library/Businessprocess/Storage/LegacyConfigRenderer.php b/library/Businessprocess/Storage/LegacyConfigRenderer.php
index 5b099fb..430a7a5 100644
--- a/library/Businessprocess/Storage/LegacyConfigRenderer.php
+++ b/library/Businessprocess/Storage/LegacyConfigRenderer.php
@@ -197,7 +197,7 @@ class LegacyConfigRenderer
         $op = static::renderOperator($node);
         $children = $node->getChildNames();
         $str = implode(' ' . $op . ' ', array_map(function ($val) {
-            return preg_replace('~([\|\+&\!\%])~', '\\\\$1', $val);
+            return preg_replace('~([\|\+&\!\%\^])~', '\\\\$1', $val);
         }, $children));
 
         if ((count($children) < 2) && $op !== '&') {