Negotiator

Noun

 * 1) One who negotiates.
 * 2) A diplomat, moderator.

Thesaurus
agent, arbitrator, bargainer, broker, business agent, cardholder, connection, contact, deputy, front, front man, go-between, interagent, interceder, intercessor, intermediary, intermediate, intermediate agent, intermediator, intermedium, internuncio, interpleader, intervener, interventionist, interventor, labor organizer, mediator, medium, middleman, mouthpiece, negotiant, negotiatress, negotiatrix, ombudsman, organizer, shop steward, spokesman, spokeswoman, trade unionist, union member, union officer, unionist