In negotiation, the disputants have sole responsibility for the outcome. The introduction of mediation does not end the negotiation. On the contrary the negotiation continues: mediation is simply an adjunct to negotiation. The disputants remain the final decision makers. The subject matter of the controversy and the time frame also remain the same. The mediator is there simply to help the negotiators get together.
A mediator is simultaneously an educator and a housekeeper. He clarifies the issues, helps gather and assess the relevant facts, suggests lines of inquiry that might be fruitful, arranges for meetings and determines how long they should last, exchanges messages and keeps the negotiations from lapsing into disarray.
The mediator has served his purpose if he has helped the parties reach an agreement. Obviously, he will not always succeed. But even in failure, it is unlikely that he will do any harm. Mediation is an art, not a science. Its conduct varies with the skills and personalities of the mediators and the effectiveness of their efforts.