diff --git a/rc/base/new-client.kak b/rc/base/new-client.kak
index 4413d6e2..6ec538a9 100644
--- a/rc/base/new-client.kak
+++ b/rc/base/new-client.kak
@@ -4,11 +4,7 @@ The ''terminal'' alias is being used to determine the user''s preferred terminal
 The optional arguments are passed as commands to the new client' \
 %{
     try %{
-        terminal %sh{
-            # double-up single-quotes
-            escaped=$(printf %s "$*" | sed -e "s|'|''|g")
-            printf "kak -c '%s' -e '%s'" "$kak_session" "$escaped"
-        }
+        terminal kak -c %val{session} -e "%arg{@}"
     } catch %{
         fail "The 'terminal' alias must be defined to use this command"
     }
diff --git a/rc/base/screen.kak b/rc/base/screen.kak
index dca8c5be..e4ddd2e9 100644
--- a/rc/base/screen.kak
+++ b/rc/base/screen.kak
@@ -9,35 +9,46 @@ hook -group GNUscreen global KakBegin .* %sh{
     "
 }
 
-define-command screen-terminal-impl -hidden -params 3 %{
+define-command screen-terminal-impl -hidden -params 3.. %{
     nop %sh{
         tty="$(ps -o tty ${kak_client_pid} | tail -n 1)"
         screen -X eval "$1" "$2"
-        screen -X screen sh -c "$3; screen -X remove" < "/dev/$tty"
+        shift 2
+        # see x11.kak for what this achieves
+        args=$(
+            for i in "$@"; do
+                if [ "$i" = '' ]; then
+                    printf "'' "
+                else
+                    printf %s "$i" | sed -e "s|'|'\\\\''|g; s|^|'|; s|$|' |"
+                fi
+            done
+        )
+        screen -X screen sh -c "${args} ; screen -X remove" < "/dev/$tty"
     }
 }
 
-define-command screen-terminal-vertical -params 1 -shell-completion -docstring '
-screen-terminal-vertical <program>: create a new terminal as a screen pane
+define-command screen-terminal-vertical -params 1.. -shell-completion -docstring '
+screen-terminal-vertical <program> [<arguments>] [<arguments>]: create a new terminal as a screen pane
 The current pane is split into two, left and right
-The shell program passed as argument will be executed in the new terminal' \
+The program passed as argument will be executed in the new terminal' \
 %{
     screen-terminal-impl 'split -v' 'focus right' %arg{@}
 }
-define-command screen-terminal-horizontal -params 1 -shell-completion -docstring '
-screen-terminal-horizontal <program>: create a new terminal as a screen pane
+define-command screen-terminal-horizontal -params 1.. -shell-completion -docstring '
+screen-terminal-horizontal <program> [<arguments>]: create a new terminal as a screen pane
 The current pane is split into two, top and bottom
-The shell program passed as argument will be executed in the new terminal' \
+The program passed as argument will be executed in the new terminal' \
 %{
     screen-terminal-impl 'split -h' 'focus down' %arg{@}
 }
-define-command screen-terminal-window -params 1 -shell-completion -docstring '
-screen-terminal-window <program>: create a new terminal as a screen window
-The shell program passed as argument will be executed in the new terminal' \
+define-command screen-terminal-window -params 1.. -shell-completion -docstring '
+screen-terminal-window <program> [<arguments>]: create a new terminal as a screen window
+The program passed as argument will be executed in the new terminal' \
 %{
     nop %sh{
         tty="$(ps -o tty ${kak_client_pid} | tail -n 1)"
-        screen -X screen sh -c "$*" < "/dev/$tty"
+        screen -X screen "$@" < "/dev/$tty"
     }
 }
 
diff --git a/rc/base/tmux.kak b/rc/base/tmux.kak
index 23a381e2..acc5c097 100644
--- a/rc/base/tmux.kak
+++ b/rc/base/tmux.kak
@@ -11,7 +11,7 @@ hook global KakBegin .* %sh{
     fi
 }
 
-define-command -hidden -params 2 tmux-terminal-impl %{
+define-command -hidden -params 2.. tmux-terminal-impl %{
     evaluate-commands %sh{
         tmux=${kak_client_env_TMUX:-$TMUX}
         if [ -z "$tmux" ]; then
@@ -19,29 +19,32 @@ define-command -hidden -params 2 tmux-terminal-impl %{
             exit
         fi
         tmux_args="$1"
-        TMUX=$tmux tmux $tmux_args env TMPDIR="$TMPDIR" sh -c "$2" < /dev/null > /dev/null 2>&1 &
+        shift
+        # ideally we should escape single ';' to stop tmux from interpreting it as a new command
+        # but that's probably too rare to care
+        TMUX=$tmux tmux $tmux_args env TMPDIR="$TMPDIR" "$@" < /dev/null > /dev/null 2>&1 &
     }
 }
 
-define-command tmux-terminal-vertical -params 1 -shell-completion -docstring '
-tmux-terminal-vertical <program>: create a new terminal as a tmux pane
+define-command tmux-terminal-vertical -params 1.. -shell-completion -docstring '
+tmux-terminal-vertical <program> [<arguments>]: create a new terminal as a tmux pane
 The current pane is split into two, top and bottom
-The shell program passed as argument will be executed in the new terminal' \
+The program passed as argument will be executed in the new terminal' \
 %{
-    tmux-terminal-impl 'split-window -v' %arg{1}
+    tmux-terminal-impl 'split-window -v' %arg{@}
 }
-define-command tmux-terminal-horizontal -params 1 -shell-completion -docstring '
-tmux-terminal-horizontal <program>: create a new terminal as a tmux pane
+define-command tmux-terminal-horizontal -params 1.. -shell-completion -docstring '
+tmux-terminal-horizontal <program> [<arguments>]: create a new terminal as a tmux pane
 The current pane is split into two, left and right
-The shell program passed as argument will be executed in the new terminal' \
+The program passed as argument will be executed in the new terminal' \
 %{
-    tmux-terminal-impl 'split-window -h' %arg{1}
+    tmux-terminal-impl 'split-window -h' %arg{@}
 }
-define-command tmux-terminal-window -params 1 -shell-completion -docstring '
-tmux-terminal-window <program> [<arguments>]: create a new terminal as a tmux window
-The shell program passed as argument will be executed in the new terminal' \
+define-command tmux-terminal-window -params 1.. -shell-completion -docstring '
+tmux-terminal-window <program> [<arguments>] [<arguments>]: create a new terminal as a tmux window
+The program passed as argument will be executed in the new terminal' \
 %{
-    tmux-terminal-impl 'new-window' %arg{1}
+    tmux-terminal-impl 'new-window' %arg{@}
 }
 
 define-command tmux-focus -params ..1 -client-completion -docstring '
diff --git a/rc/base/x11.kak b/rc/base/x11.kak
index fea97bbd..9885aa9b 100644
--- a/rc/base/x11.kak
+++ b/rc/base/x11.kak
@@ -22,16 +22,36 @@ A shell command is appended to the one set in this option at runtime} \
     done
 }
 
-define-command x11-terminal -params 1 -shell-completion -docstring '
-x11-terminal <program>: create a new terminal as an x11 window
-The shell program passed as argument will be executed in the new terminal' \
+define-command x11-terminal -params 1.. -shell-completion -docstring '
+x11-terminal <program> [<arguments>]: create a new terminal as an x11 window
+The program passed as argument will be executed in the new terminal' \
 %{
     evaluate-commands %sh{
         if [ -z "${kak_opt_termcmd}" ]; then
            echo "fail 'termcmd option is not set'"
            exit
         fi
-        setsid ${kak_opt_termcmd} "$1" < /dev/null > /dev/null 2>&1 &
+        # join arguments into a single string, in which they're delimited
+        # by single quotes, and with single quotes inside transformed to '\''
+        # so that sh -c "$args" will re-split the arguments properly
+        # example:
+        # $1 = ab
+        # $2 = foo bar
+        # $3 =
+        # $4 = foo'bar
+        # $args = 'ab' 'foo bar' '' 'foo'\''bar'
+        # would be nicer to do in a single sed/awk call but that's difficult
+        args=$(
+            for i in "$@"; do
+                # special case to preserve empty variables as sed won't touch these
+                if [ "$i" = '' ]; then
+                    printf "'' "
+                else
+                    printf %s "$i" | sed -e "s|'|'\\\\''|g; s|^|'|; s|$|' |"
+                fi
+            done
+        )
+        setsid ${kak_opt_termcmd} "$args" < /dev/null > /dev/null 2>&1 &
     }
 }
 
diff --git a/rc/extra/iterm.kak b/rc/extra/iterm.kak
index 65fdc3dc..c7e7b961 100644
--- a/rc/extra/iterm.kak
+++ b/rc/extra/iterm.kak
@@ -11,12 +11,25 @@ hook global KakBegin .* %sh{
     fi
 }
 
-define-command -hidden -params 2 iterm-terminal-split-impl %{
+define-command -hidden -params 2.. iterm-terminal-split-impl %{
     nop %sh{
-        # replace ' with '\\'' in the command
-        escaped=$(printf %s "$2" | sed -e "s|'|'\\\\\\\\''|g")
         direction="$1"
-        cmd="env PATH='${PATH}' TMPDIR='${TMPDIR}' sh -c '$escaped'"
+        shift
+        # join the arguments as one string for the shell execution (see x11.kak)
+        args=$(
+            for i in "$@"; do
+                if [ "$i" = '' ]; then
+                    printf "'' "
+                else
+                    printf %s "$i" | sed -e "s|'|'\\\\''|g; s|^|'|; s|$|' |"
+                fi
+            done
+        )
+        # go through another round of escaping for osascript
+        # \ -> \\
+        # " -> \"
+        escaped=$(printf %s "$args" | sed -e 's|\|\\\\|g; s|"|\\"|g')
+        cmd="env PATH='${PATH}' TMPDIR='${TMPDIR}' $escaped"
         osascript                                                                             \
         -e "tell application \"iTerm\""                                                       \
         -e "    tell current session of current window"                                       \
@@ -26,28 +39,38 @@ define-command -hidden -params 2 iterm-terminal-split-impl %{
     }
 }
 
-define-command iterm-terminal-vertical -params 1 -shell-completion -docstring '
-iterm-terminal-vertical <program>: create a new terminal as an iterm pane
+define-command iterm-terminal-vertical -params 1.. -shell-completion -docstring '
+iterm-terminal-vertical <program> [<arguments>]: create a new terminal as an iterm pane
 The current pane is split into two, top and bottom
-The shell program passed as argument will be executed in the new terminal'\
+The program passed as argument will be executed in the new terminal'\
 %{
     iterm-terminal-split-impl 'vertically' %arg{1}
 }
-define-command iterm-terminal-horizontal -params 1 -shell-completion -docstring '
-iterm-terminal-horizontal <program>: create a new terminal as an iterm pane
+define-command iterm-terminal-horizontal -params 1.. -shell-completion -docstring '
+iterm-terminal-horizontal <program> [<arguments>]: create a new terminal as an iterm pane
 The current pane is split into two, left and right
-The shell program passed as argument will be executed in the new terminal'\
+The program passed as argument will be executed in the new terminal'\
 %{
     iterm-terminal-split-impl 'horizontally' %arg{1}
 }
 
-define-command iterm-terminal-tab -params 1 -shell-completion -docstring '
-iterm-terminal-tab <program>: create a new terminal as an iterm tab
-The shell program passed as argument will be executed in the new terminal'\
+define-command iterm-terminal-tab -params 1.. -shell-completion -docstring '
+iterm-terminal-tab <program> [<arguments>]: create a new terminal as an iterm tab
+The program passed as argument will be executed in the new terminal'\
 %{
     nop %sh{
-        escaped=$(printf %s "$1" | sed -e "s|'|'\\\\\\\\''|g")
-        cmd="env PATH='${PATH}' TMPDIR='${TMPDIR}' sh -c '$escaped'"
+        # see above
+        args=$(
+            for i in "$@"; do
+                if [ "$i" = '' ]; then
+                    printf "'' "
+                else
+                    printf %s "$i" | sed -e "s|'|'\\\\''|g; s|^|'|; s|$|' |"
+                fi
+            done
+        )
+        escaped=$(printf %s "$args" | sed -e 's|\|\\\\|g; s|"|\\"|g')
+        cmd="env PATH='${PATH}' TMPDIR='${TMPDIR}' $escaped"
         osascript                                                       \
         -e "tell application \"iTerm\""                                 \
         -e "    tell current window"                                    \
@@ -58,12 +81,22 @@ The shell program passed as argument will be executed in the new terminal'\
 }
 
 define-command iterm-terminal-window -params 1 -shell-completion -docstring '
-iterm-terminal-window <program>: create a new terminal as an iterm window
-The shell program passed as argument will be executed in the new terminal'\
+iterm-terminal-window <program> [<arguments>]: create a new terminal as an iterm window
+The program passed as argument will be executed in the new terminal'\
 %{
     nop %sh{
-        escaped=$(printf %s "$1" | sed -e "s|'|'\\\\\\\\''|g")
-        cmd="env PATH='${PATH}' TMPDIR='${TMPDIR}' sh -c '$escaped'"
+        # see above
+        args=$(
+            for i in "$@"; do
+                if [ "$i" = '' ]; then
+                    printf "'' "
+                else
+                    printf %s "$i" | sed -e "s|'|'\\\\''|g; s|^|'|; s|$|' |"
+                fi
+            done
+        )
+        escaped=$(printf %s "$args" | sed -e 's|\|\\\\|g; s|"|\\"|g')
+        cmd="env PATH='${PATH}' TMPDIR='${TMPDIR}' $escaped"
         osascript                                                      \
         -e "tell application \"iTerm\""                                \
         -e "    create window with default profile command \"${cmd}\"" \
diff --git a/rc/extra/kitty.kak b/rc/extra/kitty.kak
index 56931423..79583945 100644
--- a/rc/extra/kitty.kak
+++ b/rc/extra/kitty.kak
@@ -12,21 +12,21 @@ hook -group kitty-hooks global KakBegin .* %sh{
     fi
 }
 
-define-command kitty-terminal -params 1 -shell-completion -docstring '
-kitty-terminal <program>: create a new terminal as a kitty window
-The shell program passed as argument will be executed in the new terminal' \
+define-command kitty-terminal -params 1.. -shell-completion -docstring '
+kitty-terminal <program> [<arguments>]: create a new terminal as a kitty window
+The program passed as argument will be executed in the new terminal' \
 %{
     nop %sh{
-        kitty @ new-window --no-response --window-type $kak_opt_kitty_window_type sh -c "$1"
+        kitty @ new-window --no-response --window-type $kak_opt_kitty_window_type "$@"
     }
 }
 
-define-command kitty-terminal-tab -params 1 -shell-completion -docstring '
-kitty-terminal-tab <program>: create a new terminal as kitty tab
-The shell program passed as argument will be executed in the new terminal' \
+define-command kitty-terminal-tab -params 1.. -shell-completion -docstring '
+kitty-terminal-tab <program> [<arguments>]: create a new terminal as kitty tab
+The program passed as argument will be executed in the new terminal' \
 %{
     nop %sh{
-        kitty @ new-window --no-response --new-tab sh -c "$1"
+        kitty @ new-window --no-response --new-tab "$@"
     }
 }