diff --git a/bin/cylc-cat-log b/bin/cylc-cat-log
index f2e6deb1c7d..20aacc8db25 100755
--- a/bin/cylc-cat-log
+++ b/bin/cylc-cat-log
@@ -51,7 +51,7 @@ if remrun(abort_if='edit', forward_x11=True):
 import os
 import shlex
 from glob import glob
-from pipes import quote
+from shlex import quote
 from stat import S_IRUSR
 from tempfile import mkstemp
 from subprocess import Popen, PIPE
diff --git a/lib/cylc/host_appointer.py b/lib/cylc/host_appointer.py
index 5cfeb360562..99fd4847328 100644
--- a/lib/cylc/host_appointer.py
+++ b/lib/cylc/host_appointer.py
@@ -19,7 +19,7 @@
 
 import json
 from itertools import dropwhile
-from pipes import quote
+from shlex import quote
 from random import choice
 import socket
 from time import sleep
diff --git a/lib/cylc/remote.py b/lib/cylc/remote.py
index 278f8869d66..c52f8651dd9 100644
--- a/lib/cylc/remote.py
+++ b/lib/cylc/remote.py
@@ -18,7 +18,7 @@
 """Run command on a remote, (i.e. a remote [user@]host)."""
 
 import os
-from pipes import quote
+from shlex import quote
 from posix import WIFSIGNALED
 import shlex
 import signal
diff --git a/lib/cylc/scheduler.py b/lib/cylc/scheduler.py
index 5b1610097d5..230466e27c3 100644
--- a/lib/cylc/scheduler.py
+++ b/lib/cylc/scheduler.py
@@ -20,7 +20,7 @@
 from collections import deque
 import logging
 import os
-from pipes import quote
+from shlex import quote
 from queue import Empty, Queue
 from shutil import copytree, rmtree
 from subprocess import Popen, PIPE
diff --git a/lib/cylc/subprocctx.py b/lib/cylc/subprocctx.py
index 1c925b81766..f5a0fb0ab96 100644
--- a/lib/cylc/subprocctx.py
+++ b/lib/cylc/subprocctx.py
@@ -21,7 +21,7 @@
 """
 
 import json
-from pipes import quote
+from shlex import quote
 
 from cylc.wallclock import get_current_time_string
 
diff --git a/lib/cylc/suite_events.py b/lib/cylc/suite_events.py
index 1d238e8cd00..52828f7c265 100644
--- a/lib/cylc/suite_events.py
+++ b/lib/cylc/suite_events.py
@@ -19,7 +19,7 @@
 
 from collections import namedtuple
 import os
-from pipes import quote
+from shlex import quote
 
 from cylc import LOG
 from cylc.cfgspec.glbl_cfg import glbl_cfg
diff --git a/lib/cylc/task_events_mgr.py b/lib/cylc/task_events_mgr.py
index 304c282281a..aed0ad18df9 100644
--- a/lib/cylc/task_events_mgr.py
+++ b/lib/cylc/task_events_mgr.py
@@ -30,7 +30,7 @@
 from collections import namedtuple
 from logging import getLevelName, CRITICAL, ERROR, WARNING, INFO, DEBUG
 import os
-from pipes import quote
+from shlex import quote
 import shlex
 from time import time
 
diff --git a/lib/cylc/task_remote_mgr.py b/lib/cylc/task_remote_mgr.py
index 4371051fae7..d5db719e650 100644
--- a/lib/cylc/task_remote_mgr.py
+++ b/lib/cylc/task_remote_mgr.py
@@ -25,7 +25,7 @@
 """
 
 import os
-from pipes import quote
+from shlex import quote
 import re
 from subprocess import Popen, PIPE
 import tarfile