diff --git a/conf/sway/config b/conf/sway/config
index e2c181ad..6f49a2f5 100644
--- a/conf/sway/config
+++ b/conf/sway/config
@@ -22,8 +22,8 @@ set $menu bemenu-run | xargs swaymsg exec --
 
 # Screen lock command
 # -c, colour, -F showing failed attempts, -k keyboard layout display,
-# -l, caps lock idnicator
-set $ScreenLockCmd swaylock -c 000000 -F -k -l
+# -l, caps lock idnicator, -f fork (required by swayidle)
+set $ScreenLockCmd swaylock -c 000000 -F -k -l -f
 
 # Preferred graphical text editor
 set $TEXTEDITOR pluma
diff --git a/conf/sway/config.d/swayidle.conf b/conf/sway/config.d/swayidle.conf
new file mode 100644
index 00000000..e56124bd
--- /dev/null
+++ b/conf/sway/config.d/swayidle.conf
@@ -0,0 +1,11 @@
+# Copied from `man swayidle`, except the $ScreenLockCmd that I don't
+# want to repeat.
+#  This will lock your screen after 300 seconds of inactivity, then turn off
+#  your displays after another 300 seconds, and turn your screens back on
+#  when resumed. It will also lock your screen before your computer goes to
+#  sleep.
+exec swayidle -w \
+     timeout 300 "\"$ScreenLockCmd\"" \
+     timeout 600 'swaymsg "output * dpms off"' \
+          resume 'swaymsg "output * dpms on"' \
+     before-sleep "\"$ScreenLockCmd\""