Reparation is an action to mitigate a loss by providing compensation to rectify the situation. This can be more difficult in practice than it sounds. For something simple like a broken window, the reparation is obvious, but reparations become more complicated when issues like emotional suffering are present, or when it is not actually possible to offer a satisfactory resolution. When a person dies in a drunk driving accident, for example, the driver at fault cannot bring her back to life.

Courts can impose reparation as part of the sentence when a matter goes to trial and a judge finds fault. People may have to pay monetary reparations, offering payments to help people replace lost items or recover from financial losses like being unable to work or losing the person responsible for a family's income. Other reparations can include community service like cleaning up graffiti or repairing other acts of vandalism.

Reparation provides people with a mechanism for compensation when they experience harm because of the activities of another person. When courts determine an appropriate sentence, they consider the amount of the loss and must come up with a reasonable amount of reparation. The court order cannot exceed the scope of the loss; for example, it a person breaks a window by throwing something at it, the judge cannot order the person to replace all the windows in the house, only the broken one.

In international law, reparation is a bone of contention in some cases. Several prominent suits have included demands to pay reparations after periods of war, genocide, or slavery, with judges ordering the nation at fault to offer restitution to people who suffered. In the case of wars, this can leave losing nations at a profound disadvantage, as in addition to being devastated by war, they can also experience severe economic hardship while they make reparations. A notable example occurred in Germany after the First World War, when the country had difficulty rebuilding infrastructure while paying reparations.

The law surrounding reparation practices is complex. Judges have a certain amount of leeway to use their best judgment in cases where compensation is necessary. People can appeal the judgment on the grounds it is excessive, although in some cases a judge may be able to include penal fines in a judgment, ordering the person to pay more as a punishment and warning to other people considering the same crime.