diff --git a/a2c_ppo_acktr/arguments.py b/a2c_ppo_acktr/arguments.py
index 0a6e70c39..315a11bd3 100644
--- a/a2c_ppo_acktr/arguments.py
+++ b/a2c_ppo_acktr/arguments.py
@@ -149,6 +149,12 @@ def get_args():
         action='store_true',
         default=False,
         help='use a linear schedule on the learning rate')
+    parser.add_argument(
+        '--disable-fork-safety',
+        action='store_true',
+        default=False,
+        help='Add an environment variable to prevent occasional '
+             'conflict with macOS fork safety')
     args = parser.parse_args()
 
     args.cuda = not args.no_cuda and torch.cuda.is_available()
diff --git a/main.py b/main.py
index 49abb59c0..6d6be45df 100755
--- a/main.py
+++ b/main.py
@@ -22,7 +22,8 @@
 
 def main():
     args = get_args()
-
+    if args.disable_fork_safety:
+        os.environ['OBJC_DISABLE_INITIALIZE_FORK_SAFETY'] = 'YES'
     torch.manual_seed(args.seed)
     torch.cuda.manual_seed_all(args.seed)