diff --git a/apps/wolfsshd/test/sshd_term_size_test.sh b/apps/wolfsshd/test/sshd_term_size_test.sh
index 2895996d..80676688 100755
--- a/apps/wolfsshd/test/sshd_term_size_test.sh
+++ b/apps/wolfsshd/test/sshd_term_size_test.sh
@@ -15,6 +15,12 @@ if [ -z "$1" ] || [ -z "$2" ]; then
     exit 1
 fi
 
+# The tmux session name is shared across everything this user runs, so it is
+# derived from the port this run was given rather than being the constant
+# "test": two concurrent runs of the suite would otherwise fight over one
+# session and the EXIT trap below would kill the other run's.
+TMUX_SESSION="wolfsshd_test_$2"
+
 # Check if tmux is available
 which tmux
 RESULT=$?
@@ -25,20 +31,20 @@ fi
 
 # tear down the tmux session on any exit, so a timeout failure does not
 # leave a stale session that breaks the next run with "duplicate session"
-trap 'tmux kill-session -t test 2>/dev/null || true' EXIT
+trap 'tmux kill-session -t "$TMUX_SESSION" 2>/dev/null || true' EXIT
 
 # Wait until the remote shell produces some output (i.e. a prompt), so the
 # SSH session is known to be up before keys are sent to it. CI runners can
 # take several seconds to get through key exchange and login.
 wait_for_session() {
     for _ in $(seq 1 10); do
-        if tmux capture-pane -p -t test | grep -q '[^[:space:]]'; then
+        if tmux capture-pane -p -t "$TMUX_SESSION" | grep -q '[^[:space:]]'; then
             return 0
         fi
         sleep 1
     done
     echo "Timed out waiting for SSH session output"
-    tmux capture-pane -p -t test
+    tmux capture-pane -p -t "$TMUX_SESSION"
     return 1
 }
 
@@ -50,30 +56,30 @@ get_size_line() {
         # Re-send the query each pass in case the shell was not yet ready to
         # read input on an earlier pass; tail -n 1 below tolerates the extra
         # numeric line a repeat can produce.
-        tmux send-keys -t test 'echo;echo $COLUMNS $LINES;echo'
-        tmux send-keys -t test 'ENTER'
+        tmux send-keys -t "$TMUX_SESSION" 'echo;echo $COLUMNS $LINES;echo'
+        tmux send-keys -t "$TMUX_SESSION" 'ENTER'
         sleep 1
-        SIZE_LINE=$(tmux capture-pane -p -t test | tr -d '\r' | \
+        SIZE_LINE=$(tmux capture-pane -p -t "$TMUX_SESSION" | tr -d '\r' | \
             grep -E '^[0-9]+[[:space:]]+[0-9]+[[:space:]]*$' | tail -n 1)
         if [ -n "$SIZE_LINE" ]; then
             return 0
         fi
     done
     echo "Timed out waiting for terminal size output"
-    tmux capture-pane -p -t test
+    tmux capture-pane -p -t "$TMUX_SESSION"
     return 1
 }
 
 echo "Creating tmux session at $PWD with command :"
-echo "tmux new-session -d -s test \"$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\"\""
-tmux new-session -d -s test "$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\""
+echo "tmux new-session -d -s $TMUX_SESSION \"$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\"\""
+tmux new-session -d -s "$TMUX_SESSION" "$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\""
 echo "Result of tmux new-session = $?"
 
 wait_for_session || exit 1
 
-COL=`tmux display -p -t test '#{pane_width}'`
-ROW=`tmux display -p -t test '#{pane_height}'`
-echo "tmux 'test' session has COL = ${COL} and ROW = ${ROW}"
+COL=`tmux display -p -t "$TMUX_SESSION" '#{pane_width}'`
+ROW=`tmux display -p -t "$TMUX_SESSION" '#{pane_height}'`
+echo "tmux $TMUX_SESSION session has COL = ${COL} and ROW = ${ROW}"
 
 # get the terminals columns and lines
 get_size_line || exit 1
@@ -94,20 +100,20 @@ fi
 # resize tmux after connection is open is not working @TODO
 #tmux set-window-option -g aggressive-resize
 #printf '\e[8;50;100t'
-#tmux resize-pane -x 50 -y 10 -t test
+#tmux resize-pane -x 50 -y 10 -t "$TMUX_SESSION"
 
 # close down the SSH session
-tmux send-keys -t test 'exit'
-tmux send-keys -t test 'ENTER'
+tmux send-keys -t "$TMUX_SESSION" 'exit'
+tmux send-keys -t "$TMUX_SESSION" 'ENTER'
 
 # kill off the session if it's still running, but don't error out if the session
 # has already closed down
-tmux kill-session -t test
+tmux kill-session -t "$TMUX_SESSION"
 set -e
 
 echo "Starting another session with a smaller window size"
-echo "tmux new-session -d -x 50 -y 10 -s test \"$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\"\""
-tmux new-session -d -x 50 -y 10 -s test "$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\""
+echo "tmux new-session -d -x 50 -y 10 -s $TMUX_SESSION \"$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\"\""
+tmux new-session -d -x 50 -y 10 -s "$TMUX_SESSION" "$TEST_CLIENT -q -t -u $USER -i $PRIVATE_KEY -j $PUBLIC_KEY -h \"$1\" -p \"$2\""
 
 wait_for_session || exit 1
 
@@ -128,10 +134,10 @@ if [ "10" != "$ROW_FOUND" ]; then
 fi
 
 # close down the SSH session
-tmux send-keys -t test 'exit'
-tmux send-keys -t test 'ENTER'
+tmux send-keys -t "$TMUX_SESSION" 'exit'
+tmux send-keys -t "$TMUX_SESSION" 'ENTER'
 set +e
-tmux kill-session -t test
+tmux kill-session -t "$TMUX_SESSION"
 
 popd
 exit 0