diff --git a/system2mqtt.py b/system2mqtt.py
index 191727b..77250ad 100644
--- a/system2mqtt.py
+++ b/system2mqtt.py
@@ -13,6 +13,7 @@ from typing import Dict, Any, List
 import importlib.util
 import glob
 from datetime import datetime, timedelta
+from pathlib import Path
 
 # Default configuration values used when config file or env vars are missing
 CONFIG_DEFAULTS = {
@@ -31,7 +32,7 @@ CONFIG_DEFAULTS = {
 }
 
 class System2MQTT:
-    def __init__(self, config_path: str = "config.yaml"):
+    def __init__(self, config_path: str = None):
         self.config = self._load_config(config_path)
         self.hostname = socket.gethostname()
         self.client = None  # paho MQTT client initialized in connect()
@@ -40,15 +41,36 @@ class System2MQTT:
         self.collectors = self._load_collectors()
         self.last_run = {}  # Speichert den Zeitpunkt des letzten Laufs für jeden Sammler
 
-    def _load_config(self, config_path: str) -> Dict[str, Any]:
+    def _get_default_config_path(self) -> str:
+        """Get default config path following XDG Base Directory Specification.
+        
+        Returns path in order of preference:
+        1. $XDG_CONFIG_HOME/system2mqtt/config.yaml
+        2. ~/.config/system2mqtt/config.yaml (if XDG_CONFIG_HOME not set)
+        """
+        xdg_config_home = os.environ.get('XDG_CONFIG_HOME')
+        if xdg_config_home:
+            config_dir = Path(xdg_config_home) / 'system2mqtt'
+        else:
+            config_dir = Path.home() / '.config' / 'system2mqtt'
+        
+        return str(config_dir / 'config.yaml')
+
+    def _load_config(self, config_path: str = None) -> Dict[str, Any]:
         """Load configuration from YAML file, apply defaults and environment overrides.
 
         Precedence: CONFIG_DEFAULTS < config file < environment variables
+        Config path precedence: SYSTEM2MQTT_CONFIG env var > parameter > XDG location
         """
-        # Determine config path: env var overrides parameter
+        # Determine config path with precedence:
+        # 1. SYSTEM2MQTT_CONFIG environment variable
+        # 2. Provided config_path parameter
+        # 3. XDG Base Directory Specification location
         env_path = os.environ.get('SYSTEM2MQTT_CONFIG')
         if env_path:
             config_path = env_path
+        elif config_path is None:
+            config_path = self._get_default_config_path()
 
         config = {}
         # Start with defaults