This monograph provides readers with a basic knowledge of the principles governing agency relationships under common law. The main body covers topics ranging from the creation of agency, duties of an agent, rights and obligations among principals, agents and third parties, to termination of agency. Estate agents, in acting for their principals (that is, clients), are subject to common law principles like any other agent. However, common law is only one of the legal sources governing the conduct and duties of agents. In Hong Kong, estate agents are also subject to the Estate Agents Ordinance (EAO) (Cap. 511) and its subsidiary legislation. Whenever there is a conflict between common law and statute law, statute law prevails.

In addition to the requirements under the EAO and its subsidiary legislation, estate agency practitioners are also subject to the Code of Ethics and Practice Circulars issued from time to time by the Estate Agents Authority (EAA). Though not legally binding per se, these directives reflect standards of good practice and may have implications on a licensee's fitness to hold a licence. The last section of this monograph summarises the major requirements of estate agents under the EAO and its subsidiary legislation.