diff --git a/torchy_baselines/common/base_class.py b/torchy_baselines/common/base_class.py
index 09fe798..384ad27 100644
--- a/torchy_baselines/common/base_class.py
+++ b/torchy_baselines/common/base_class.py
@@ -169,10 +169,20 @@ class BaseRLModel(object):
     def set_env(self, env):
         """
         Checks the validity of the environment, and if it is coherent, set it as the current environment.
+        checked parameters:
+         - observation_space
+         - action_space
 
         :param env: (Gym Environment) The environment for learning a policy
         """
-        pass
+
+        if self.observation_space != env.observation_space:
+            raise ValueError("The given environment has a observation_space that doesn't fit the current model")
+
+        if self.action_space != env.action_space:
+            raise ValueError("The given environment has a action_space that doesn't fit the current model")
+        # if all fits save new env
+        self.env = env
 
     def get_parameter_list(self):
         """