Combine the benefits of ear buds (hearing your surroundings) with the benefits of in-ear (noise reduction) headphones.
In-ear headphones that can block or pass through the surrounding sounds controlled by the user.
Get live help in your ear when (after training) they start working in their new job (sales, services etc.)
Have a concealed in-ear piece transmitting what they hear to the live-helper and receiving real-time help from him.