Authors Mittenthal and Bloch examine how arbitrators, in performing their interpretive function, find implied obligations that are nowhere mentioned in the contract. Arbitrators embrace those implications that help to preserve the parties’ bargain and reject those that alter or enlarge it. Author Macey agrees that preserving the parties’ bargain should be a guiding concern, but notes that many implied rights appear to be founded, not upon the parties’ bargain, but upon an unwillingness by the arbitrator to interfere with management’s operational decisions. Author Tabler comments that it is not the role of arbitrators to infer promises or impose presumptions. Arbitral implications, she argues, are unfair to management; they undermine the arbitration and the negotiation process and, ultimately, may hurt the employees.