Issue preclusion, also known as collateral estoppel, prevents a party from relitigating an issue that has already been judged in a final verdict in a previous case. This legal principle ensures that once a court has decided an issue of fact or law, it cannot be disputed again in future litigation involving the same parties. Issue preclusion promotes judicial efficiency and consistency by avoiding redundant litigation over the same issue and protecting parties from the burden of having to relitigate settled matters.