diff --git a/ipsframework/ips.py b/ipsframework/ips.py
index 4ce8b8c0..beea2556 100755
--- a/ipsframework/ips.py
+++ b/ipsframework/ips.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python3
+#!/usr/bin/env python3
 # -------------------------------------------------------------------------------
 # Copyright 2006-2021 UT-Battelle, LLC. See LICENSE for more information.
 # -------------------------------------------------------------------------------
diff --git a/ipsframework/ips_dakota_client.py b/ipsframework/ips_dakota_client.py
index 46a6c296..f1180bc2 100755
--- a/ipsframework/ips_dakota_client.py
+++ b/ipsframework/ips_dakota_client.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#!/usr/bin/env python3
 # -------------------------------------------------------------------------------
 # Copyright 2006-2021 UT-Battelle, LLC. See LICENSE for more information.
 # -------------------------------------------------------------------------------
diff --git a/ipsframework/ips_dakota_dynamic.py b/ipsframework/ips_dakota_dynamic.py
index 6edfdb7c..5ac89375 100755
--- a/ipsframework/ips_dakota_dynamic.py
+++ b/ipsframework/ips_dakota_dynamic.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # -------------------------------------------------------------------------------
 # Copyright 2006-2021 UT-Battelle, LLC. See LICENSE for more information.
 # -------------------------------------------------------------------------------
diff --git a/ipsframework/portalBridge.py b/ipsframework/portalBridge.py
index d3ddae8d..6a1e3d21 100644
--- a/ipsframework/portalBridge.py
+++ b/ipsframework/portalBridge.py
@@ -255,7 +255,7 @@ def send_event(self, sim_data, event_data):
             try:
                 if self.first_event:  # First time, launch sendPost.py daemon
                     cmd = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'sendPost.py')
-                    python_exec = shutil.which('python')
+                    python_exec = shutil.which('python3')
                     self.childProcess = Popen([python_exec, cmd], bufsize=128,
                                               stdin=PIPE, stdout=PIPE,
                                               stderr=PIPE, close_fds=True)
diff --git a/ipsframework/sendPost.py b/ipsframework/sendPost.py
index 5d1bf64c..5eef2bac 100644
--- a/ipsframework/sendPost.py
+++ b/ipsframework/sendPost.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # -------------------------------------------------------------------------------
 #  Copyright 2006-2021 UT-Battelle, LLC. See LICENSE for more information.
 # -------------------------------------------------------------------------------
diff --git a/ipsframework/utils/HTML.py b/ipsframework/utils/HTML.py
index 3c34edd7..2da6f0c4 100755
--- a/ipsframework/utils/HTML.py
+++ b/ipsframework/utils/HTML.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
 # -*- coding: iso-8859-1 -*-
 """
 HTML.py - v0.04 2009-07-28 Philippe Lagadec