diff --git a/plexpy/common.py b/plexpy/common.py
index 039931f4..b6800d3c 100644
--- a/plexpy/common.py
+++ b/plexpy/common.py
@@ -679,3 +679,8 @@ NEWSLETTER_PARAMETERS = [
         ]
     }
 ]
+
+
+NOTIFICATION_PARAMETERS_TYPES = {
+    parameter['value']: parameter['type'] for category in NOTIFICATION_PARAMETERS for parameter in category['parameters']
+}
diff --git a/plexpy/notification_handler.py b/plexpy/notification_handler.py
index ad774fa6..315bcb52 100644
--- a/plexpy/notification_handler.py
+++ b/plexpy/notification_handler.py
@@ -288,7 +288,7 @@ def notify_custom_conditions(notifier_id=None, parameters=None):
                 continue
 
             # Make sure the condition values is in a list
-            if isinstance(values, str):
+            if not isinstance(values, list):
                 values = [values]
 
             # Cast the condition values to the correct type
@@ -302,6 +302,9 @@ def notify_custom_conditions(notifier_id=None, parameters=None):
                 elif parameter_type == 'float':
                     values = [helpers.cast_to_float(v) for v in values]
 
+                else:
+                    raise ValueError
+
             except ValueError as e:
                 logger.error("Tautulli NotificationHandler :: {%s} Unable to cast condition '%s', values '%s', to type '%s'."
                              % (i+1, parameter, values, parameter_type))
@@ -318,6 +321,9 @@ def notify_custom_conditions(notifier_id=None, parameters=None):
                 elif parameter_type == 'float':
                     parameter_value = helpers.cast_to_float(parameter_value)
 
+                else:
+                    raise ValueError
+
             except ValueError as e:
                 logger.error("Tautulli NotificationHandler :: {%s} Unable to cast parameter '%s', value '%s', to type '%s'."
                              % (i+1, parameter, parameter_value, parameter_type))
diff --git a/plexpy/notifiers.py b/plexpy/notifiers.py
index b7ee4f17..ffe3d40a 100644
--- a/plexpy/notifiers.py
+++ b/plexpy/notifiers.py
@@ -112,7 +112,12 @@ AGENT_IDS = {'growl': 0,
              'gotify': 29
              }
 
-DEFAULT_CUSTOM_CONDITIONS = [{'parameter': '', 'operator': '', 'value': ''}]
+DEFAULT_CUSTOM_CONDITIONS = [{'parameter': '', 'operator': '', 'value': [], 'type': None}]
+CUSTOM_CONDITION_TYPE_OPERATORS = {
+    'float': ['is', 'is not', 'is greater than', 'is less than'],
+    'int': ['is', 'is not', 'is greater than', 'is less than'],
+    'str': ['contains', 'does not contain', 'is', 'is not', 'begins with', 'does not begin with', 'ends with', 'does not end with'],
+}
 
 
 def available_notification_agents():
@@ -642,13 +647,18 @@ def set_notifier_config(notifier_id=None, agent_id=None, **kwargs):
 
     agent_class = get_agent_class(agent_id=agent['id'], config=notifier_config)
 
+    custom_conditions = validate_conditions(kwargs.get('custom_conditions'))
+    if custom_conditions is False:
+        logger.error("Tautulli Notifiers :: Unable to update notification agent: Invalid custom conditions.")
+        return False
+
     keys = {'id': notifier_id}
     values = {'agent_id': agent['id'],
               'agent_name': agent['name'],
               'agent_label': agent['label'],
               'friendly_name': kwargs.get('friendly_name', ''),
               'notifier_config': json.dumps(agent_class.config),
-              'custom_conditions': kwargs.get('custom_conditions', json.dumps(DEFAULT_CUSTOM_CONDITIONS)),
+              'custom_conditions': json.dumps(custom_conditions or DEFAULT_CUSTOM_CONDITIONS),
               'custom_conditions_logic': kwargs.get('custom_conditions_logic', ''),
               }
     values.update(actions)
@@ -685,6 +695,66 @@ def send_notification(notifier_id=None, subject='', body='', notify_action='', n
         logger.debug("Tautulli Notifiers :: Notification requested but no notifier_id received.")
 
 
+def validate_conditions(custom_conditions):
+    if custom_conditions is None:
+        return DEFAULT_CUSTOM_CONDITIONS
+
+    try:
+        conditions = json.loads(custom_conditions)
+    except ValueError:
+        logger.error("Tautulli Notifiers :: Unable to parse custom conditions json: %s" % custom_conditions)
+        return False
+
+    if not isinstance(conditions, list):
+        logger.error("Tautulli Notifiers :: Invalid custom conditions: %s. Conditions must be a list." % conditions)
+        return False
+
+    validated_conditions = []
+
+    for condition in conditions:
+        validated_condition = DEFAULT_CUSTOM_CONDITIONS[0].copy()
+
+        if not isinstance(condition, dict):
+            logger.error("Tautulli Notifiers :: Invalid custom condition: %s. Condition must be a dict." % condition)
+            return False
+
+        parameter = str(condition.get('parameter', '')).lower()
+        operator = str(condition.get('operator', '')).lower()
+        values = condition.get('value', [])
+
+        if parameter:
+            parameter_type = common.NOTIFICATION_PARAMETERS_TYPES.get(parameter)
+        
+            if not parameter_type:
+                logger.error("Tautulli Notifiers :: Invalid parameter '%s' in custom condition: %s" % (parameter, condition))
+                return False
+
+            validated_condition['parameter'] = parameter.lower()
+            validated_condition['type'] = parameter_type
+
+        if operator:
+            if operator not in CUSTOM_CONDITION_TYPE_OPERATORS.get(parameter_type, []):
+                logger.error("Tautulli Notifiers :: Invalid operator '%s' for parameter '%s' in custom condition: %s" % (operator, parameter, condition))
+                return False
+
+            validated_condition['operator'] = operator
+
+        if values:
+            if not isinstance(values, list):
+                values = [values]
+
+            for value in values:
+                if not isinstance(value, (str, int, float)):
+                    logger.error("Tautulli Notifiers :: Invalid value '%s' for parameter '%s' in custom condition: %s" % (value, parameter, condition))
+                    return False
+            
+            validated_condition['value'] = values
+
+        validated_conditions.append(validated_condition)
+
+    return validated_conditions
+
+
 def blacklist_logger():
     db = database.MonitorDatabase()
     notifiers = db.select('SELECT notifier_config FROM notifiers')