diff --git a/src/eddn/Validator.py b/src/eddn/Validator.py
index 2c8eff5..b2c6c59 100644
--- a/src/eddn/Validator.py
+++ b/src/eddn/Validator.py
@@ -3,11 +3,19 @@ from enum import IntEnum
 
 class Validator(object):
 
+    schemas = {}
+
     def validate(self, json_object):
         results = ValidationResults()
 
         if "$schemaRef" not in json_object:
             results.add(ValidationSeverity.FATAL, JsonValidationException("No $schemaRef found, unable to validate."))
+            return results
+
+        schemaRef = json_object["$schemaRef"]
+        if schemaRef not in self.schemas.keys():
+            #  We don't want to go out to the Internet and retrieve unknown schemas.
+            results.add(ValidationSeverity.FATAL, JsonValidationException("Schema " + schemaRef + " is unknown, unable to validate."))
 
         return results