The plaintiffs owned property that adjoined a golf course built and operated by the defendants. The golf course was constructed as part of a planned unit development covering 1,450 acres and included residential homes. The development occurred over a ten year period that included a significant amount of time negotiating with the plaintiffs and other surrounding neighbors. As part of the negotiations, the plaintiffs requested the defendants relocate the single family homes originally proposed to abut the plaintiffs’ property, and replace them with a fairway. The plaintiffs further requested that the defendants not build a bike path bordering their property. The plaintiffs signed an agreement with the defendants for the construction of a fence along the property line. The agreement provided that no homes would be constructed with 100 feet of the plaintiffs’ property and no bicycle path would be constructed. If the defendants complied with the agreement, the plaintiffs agreed not to protest the approval of the development. The development was completed, and the operation of the golf course resulted in golf balls continually landing on the plaintiffs’ property. The plaintiffs sued the defendants for intentional trespass and intentional private nuisance. The trial court ruled that the golf course was not a nuisance. The plaintiffs appealed to the Illinois Court of Appeals, which affirmed. The plaintiffs then appealed to the Illinois Supreme Court.