Русско-англо-русский юридический словарь

Generally, agents are under a duty to obey the lawful and reasonable instructions of the principal. Where the principal's instructions are clear, the agent does not normally have any discretion and must follow those instructions, unless an agent is a professional and the principal relies on the agent to exercise his professional skill and discretion in accomplishing the tasks he has been appointed to accomplish. (website of Hong Kong's Estate Agents Authority)