Contract Act (Cap. 32): Primary legislation governing contract formation, validity, and enforcement in Singapore. Essential for ensuring the permission letter meets basic contractual requirements.

Land Titles Act (Cap. 157): Relevant if the permission relates to property usage or real estate matters. Governs land ownership and rights in Singapore.

Planning Act (Cap. 232): Applicable if permission involves land use or development. Controls development and use of land and buildings in Singapore.

State Lands Act (Cap. 314): Relevant for permissions involving state land or properties. Governs the administration and management of State lands in Singapore.

Personal Data Protection Act 2012: Ensures compliance with data protection requirements if personal information is included in the permission letter.

Business Names Registration Act 2014: Applicable if the permission relates to business operations or use of business names.

Copyright Act: Relevant for permissions involving intellectual property rights, particularly copyrighted materials.

Trade Marks Act: Applicable when permission involves use of trademarks or branded content.

Building Control Act: Necessary consideration if permission relates to construction or building modifications.

Limitation Act (Cap. 163): Sets time limits for enforcement of rights and legal actions related to the permission.

Electronic Transactions Act: Governs electronic signatures and digital execution of documents if the permission letter is to be executed electronically.