diff --git a/zsh/config/functions/tns b/zsh/config/functions/tns
new file mode 100755
index 0000000..3d57307
--- /dev/null
+++ b/zsh/config/functions/tns
@@ -0,0 +1,44 @@
+#!/usr/bin/env zsh
+
+# Create a tmux session.
+#
+# This accepts a path argument that is used to create the tmux session
+# in, using it's basename for the session name.
+#
+# If an argument is not supplied, then we will create a tmux session in
+# the current working directory.
+
+function tns() {
+
+  local session_name=
+  local tmux_dir=
+
+  # parse the session, if based on the directory of the argument passed in.
+  # otherwise use the current directory.
+  [ -n "$1" ] && \
+    session_name=$(basename "$1" | tr . _) && \
+    tmux_dir="$1"
+
+  [ -z "$session_name" ] \
+    && session_name=$(basename "$PWD" | tr . _) && \
+    tmux_dir="$PWD"
+
+  tmux_running=$(pgrep tmux)
+
+  # check if tmux is not running / attached to a session.
+  # if not, then create a new session.
+  if [ -z $TMUX ] && [ -z $tmux_running ]; then
+    tmux new-session -s "$session_name" -c "$tmux_dir" && return 0
+  fi
+
+  # create a session if it doesn't exist, in the background, so
+  # that we can switch sessions.
+  if ! tmux has-session -t "$session_name" 2> /dev/null; then
+    tmux new-session -ds "$session_name" -c "$tmux_dir"
+  fi
+
+  # attach to the session or switch if it already exists.
+  [ -z $TMUX ] && \
+    tmux attach -t "$session_name" \
+  || tmux switch-client -t "$session_name"
+}