In law, a summary judgment (also judgement as a matter of law) is a judgment entered by a court for one party and against another party summarily, i.e., without a full trial. Such a judgment may be issued on the merits of an entire case, or on discrete issues in that case.

In common-law systems, questions about what the law actually is in a particular case are decided by judges; in rare cases jury nullification of the law may act to contravene or complement the instructions or orders of the judge, or other officers of the court. A factfinder has to decide what the facts are and apply the law. In traditional common law the factfinder was a jury, but in many jurisdictions the judge now acts as the factfinder as well. It is the factfinder who decides "what really happened," and it is the judge who applies the law to the facts as determined by the factfinder, whether directly or by giving instructions to the jury.

Absent an award of summary judgment (or some type of pretrial dismissal), a lawsuit will ordinarily proceed to trial, which is an opportunity for litigants to present evidence in an attempt to persuade the factfinder that they are saying "what really happened," and that, under the applicable law, they should prevail.