Performance of Sale (Sections 31-52) governs delivery and payment obligations. Delivery (Sections 31-43): Means voluntary transfer of possession. Types: Actual (physical handover), Constructive (acts making possession available), Symbolic (delivery of means/key). Seller's obligation: Deliver goods at contract place and time; if time not specified, reasonable time applies. Buyer's obligation: Accept goods and pay price. Payment timing: Coincides with delivery unless otherwise agreed. Partial delivery: Buyer can refuse part only if material breach. Case law: Vicar of Ashford v. Popham establishes delivery scope. Documents of title: Delivery of bill of lading/warehouse receipt constitutes delivery. For accountants, understanding delivery critical for revenue recognition—IFRS requires transfer of control which aligns with delivery timing. Risk of loss passes with delivery unless otherwise agreed. Exam tip: Identify delivery type and timing; distinguish between accepting goods and accepting invoice; apply payment condition variations.