Vincent N. Trimarco (plaintiff) was injured when a glass bathtub shower door enclosure shattered in his apartment while he was sliding the door open to exit the tub. The door was made out of ordinary glass, however, Trimarco assumed it was made out of tempered, shatterproof safety glass. Trimarco sued Klein (defendant), the owner of the building for negligence. At trial, Trimarco presented expert testimony that shatterproof glass doors have been in common use since the early 1950s and that the door at issue did not conform to accepted safety standards. Additionally, at Klein’s managing agent testified that since 1965 it was customary to replace glass shower doors with material such as plastic or safety glass. Trimarco won a verdict in his favor. Klein appealed to the Appellate Division, which reversed the decision of the trial court based on the law. The Appellate Division found that even assuming a custom and practice to use shatterproof glass, unless Klein had prior notice of the dangerousness of ordinary glass either from Trimarco or from prior accidents, Klein had no duty to replace the glass. Accordingly, the Appellate Division dismissed the complaint. Trimarco appealed to the Court of Appeals of New York.