Legal expenses insurance (LEI) covers all or a part of financial expenses occurring during a lawsuit, in exchange for the payment of a premium by the policyholder to the insurer. It makes access to justice less expensive by shifting the litigation costs from the litigant to the insurer. LEI covers many types of conflicts (labor litigations, consumer disputes, personal injuries, or medical malpractices), but some are generally excluded (divorces). LEI could have some significant effects on conflict resolution, not only for the litigants themselves but also for society. Thus, in the law and economics literature, three topics are generally studied: the consequences of LEI on conflict resolution and social welfare, the influence of the insurer in the litigation, and finally the access to justice by a comparative approach between LEI and legal aid and contingent fees.