JSI Tip 5208. How do I use the shadow command to remotely monitor and control another user's Terminal Services session?

Microsoft Knowledge Base Article 320191 contains the following summary:

This step-by-step article describes how to use the shadow command to remotely monitor and control another user's Terminal Services session. You can use the shadow command to view or actively control an active session of another user. If you actively control a user's session, you can input keyboard and mouse actions for that session.