Contract and Commercial Law Act (Cap. 53A): Primary legislation governing contract formation, validity, and enforcement in Singapore

Sale of Goods Act (Cap. 393): Regulates contracts for the sale of goods, including terms, conditions, and rights of parties

Supply of Goods Act: Governs the supply of goods and related transactions, including quality standards and implied terms

Electronic Transactions Act: Provides legal framework for electronic contracts and digital signatures in Singapore

Consumer Protection (Fair Trading) Act: Protects consumer interests against unfair practices and provides remedies for unfair transactions

Consumer Protection (Trade Descriptions and Safety Requirements) Act: Ensures accurate product descriptions and maintains safety standards for consumer goods

Unfair Contract Terms Act: Regulates unfair terms in contracts and limits the extent to which liability can be excluded

Personal Data Protection Act: Governs the collection, use, and disclosure of personal data in commercial transactions

Competition Law: Ensures fair competition and prevents anti-competitive practices in commercial arrangements

Goods and Services Tax Act: Regulates the taxation aspects of commercial transactions in Singapore

Common Law Principles: Established case law principles regarding contract modification and variation requirements

Doctrine of Consideration: Legal principle requiring new consideration for contract variations to be legally binding

Industry-Specific Regulations: Specific regulations applicable to particular industries or types of goods/services

Import/Export Regulations: Rules governing international trade and cross-border purchases if applicable