diff --git a/README.md b/README.md
index a587860..e90ac89 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,9 @@ Make sure that you have a python environment with the following packages install
 pynetbox
 pyzabbix
 ```
+### Config file
+First time user? Copy the config.py.example file to config.py. This file is used for modifying filters and setting variables such as custom field names.
+
 ### Cloning the repository
 ```
 git clone https://github.com/TheNetworkGuy/netbox-zabbix-sync.git
diff --git a/config.py.example b/config.py.example
new file mode 100644
index 0000000..9009d1b
--- /dev/null
+++ b/config.py.example
@@ -0,0 +1,17 @@
+# Set template and device Netbox "custom field" names
+template_cf = "zabbix_template"
+device_cf = "zabbix_hostid"
+
+# Netbox to Zabbix device state convertion
+zabbix_device_removal = ["Decommissioning", "Inventory"]
+zabbix_device_disable = ["Offline", "Planned", "Staged", "Failed"]
+
+# Custom filter for device filtering. Variable must be present but can be left empty with no filtering.
+# A couple of examples are as follows:
+
+# nb_device_filter = {} #No filter
+# nb_device_filter = {"tag": "zabbix"} #Use a tag
+# nb_device_filter = {"site": "HQ-AMS"} #Use a site name
+
+# Default device filter, only get devices which have a name in Netbox.
+nb_device_filter = {"name__n": "null"}
\ No newline at end of file
diff --git a/netbox_zabbix_sync.py b/netbox_zabbix_sync.py
index 60decf0..4ab8acb 100755
--- a/netbox_zabbix_sync.py
+++ b/netbox_zabbix_sync.py
@@ -1,11 +1,16 @@
 #!/usr/bin/python3
 """Netbox to Zabbix sync script."""
 
-from os import environ, path
+from os import environ, path, sys
 import logging
 import argparse
 from pynetbox import api
 from pyzabbix import ZabbixAPI, ZabbixAPIException
+try:
+    from config import *
+except ModuleNotFoundError:
+    print(f"Configuration file config.py not found in main directory. Please create the file or rename the config.py.example file to config.py.")
+    sys.exit(0)
 
 # Set logging
 log_format = logging.Formatter('%(asctime)s - %(name)s - '
@@ -24,14 +29,6 @@ logger.addHandler(lgout)
 logger.addHandler(lgfile)
 logger.setLevel(logging.WARNING)
 
-# Set template and device Netbox "custom field" names
-template_cf = "zabbix_template"
-device_cf = "zabbix_hostid"
-
-# Netbox to Zabbix device state convertion
-zabbix_device_removal = ["Decommissioning", "Inventory"]
-zabbix_device_disable = ["Offline", "Planned", "Staged", "Failed"]
-
 
 def main(arguments):
     """Run the sync process."""
@@ -75,7 +72,7 @@ def main(arguments):
         e = f"Zabbix returned the following error: {str(e)}."
         logger.error(e)
     # Get all Zabbix and Netbox data
-    netbox_devices = netbox.dcim.devices.filter(name__n="null")
+    netbox_devices = netbox.dcim.devices.filter(**nb_device_filter)
     netbox_journals = netbox.extras.journal_entries
     zabbix_groups = zabbix.hostgroup.get(output=['groupid', 'name'])
     zabbix_templates = zabbix.template.get(output=['templateid', 'name'])