Kunzman (P) sold property to McNabb. McNabb assigned `all of [his] right, title and interest' in the property to D, with the approval of Ps. All dealings on the contract were between P and D; McNabb was no longer involved. Ds took possession of the property and exercised exclusive control over it. In 1979, D's' attorney threatened Ps with legal action if they did not release deeds to certain parcels in accordance with the contract's lot release provisions. In 1984, Ds defaulted and Ps accelerated the contract balance and commenced this action. The courts granted specific performance to P and D appealed.