Formal proof hearing — whether contractual variation was enforceable — Stilk v Myrick (1809) 170 ER 1168 — Cook Island Shipping Co Limited v Colson Builders Limited [1975] 1 NZLR 422 — Williams v Roffey Bros and Nicholls (Contractors) Limited [1991] 1 QB 1. A contractual variation was found to be unenforceable, as a promise by one party to perform that party's already existing obligations under a contract does not normally constitute valid consideration ("Stilk" and "Cook Island Shipping"). The case of "Williams" was distinguished as no benefit "in practice" was obtained by accepting the variation. Accordingly, the variation clause was unenforceable for want of consideration, and the plaintiff was entitled to be repaid the sum of $57,235.92 together with interest and costs. Judgment Date: 29 November 2016.