Crane Neck Farm was a development of residential properties that were all subject to a series of restrictive covenants, one of which was a requirement that only single-family dwellings would be allowed on each lot. In 1980, the New York City/Long Island County Services Group (county services) (defendant) leased a six-bedroom home in Crane Neck Farm to use as a residential home and treatment facility for eight developmentally disabled adults. The residents of the home, who had previously been institutionalized, were offered extensive developmental and occupational therapy in a home-like setting and were under constant professional supervision. The Crane Neck Association Inc. (the association) (plaintiffs) was made up of Crane Neck property owners. The association brought a complaint against county services, alleging that the residential facility violated the single-family dwelling covenant and seeking to enforce the covenant and enjoining the continuation of the lease. The lower court granted partial summary judgment to the association, finding that the facility did not amount to a single-family dwelling and therefore violated the covenant but that there remained factual issues of whether the covenant was still valid. The matter then came before the appellate division. That court reversed the lower court and dismissed the complaint, holding that the facility did amount to a single-family residence as operated and that, in any event, the covenant could not be enforced against the facility because doing so would violate public policy. The association appealed.