Med-Arb combines mediation and arbitration in sequence: the parties first attempt a mediated settlement with a neutral mediator, and if some or all issues remain unresolved, the process converts to binding arbitration to decide what mediation could not settle.
A key design choice is whether the same person acts as both mediator and arbitrator. Using the same neutral saves time and cost but raises a real concern — information shared candidly during mediation, on the understanding it would not affect a binding decision, may consciously or unconsciously influence that same person's later ruling as arbitrator. Many institutional Med-Arb procedures address this by using a different person for each stage, or by requiring the parties' informed consent to a single neutral performing both roles.
Med-Arb suits parties who want a genuine chance at a negotiated outcome without losing the certainty of a binding decision if that chance doesn't materialise.