A Tremere Lord rules over a special geographic or disciplinary area, often called a Realm. Within the Realm, he supervises all chantries that are rooted in his area of actuation, ensuring that inter-clan businesses within run smoothly. A Lord answers to his Pontifex and can command any Regents or Apprentices within his Realm.
Most Lords communicate with their underlings via mystical means, written direction or similar methods. Few Regents ever see their superiors face-to-face.