Book excerpt: Negotiating on Behalf of Others offers a framework for understanding the complexity and effects of negotiating on behalf of others and explores how current negotiation theory can be modified to account for negotiation agents. Negotiation agents are broadly defined to include legislators, diplomats, salespersons, sports agents, attorneys, and committee chairs—anyone who represents others in a negotiation. Five major negotiation arenas are examined in depth: labor-management relations, international diplomacy, sports agents, legislative process, and agency law. The book concludes with suggestions for future research and specific advice for practitioners. Chapter authors and commentators are leading figures in the field of negotiation. Negotiating on Behalf of Others is a must read for professional negotiators, graduate students, and scholars in the areas of business, public policy, law, international relations, sports, and economics. Negotiating on Behalf of Others is the result of the first of a series of seminars conducted by the faculty of the Program on Negotiation at Harvard on "complicating factors" in negotiations. The first of these complicating factors selected for study was the effect of the presence of an agent on the negotiating process.