The employee must take all reasonable steps to carry out what has been promised under the contract of employment. Sometimes this is described as the duty to obey the lawful and reasonable orders of the employer, which usually means getting on with the work when there is work to be done and fitting in, as far as is reasonable, with the employer's scheme of operation.

The employee must exercise reasonable care and skill in the performance of the work; in other words, the employee has the duty to be efficient and to avoid negligence in doing their work.

The employee must do the job honestly and faithfully. This includes the duty to account for any property used and to pass on to the employer any profits made through the employment. 'Tips' received by many employees belong in law to the employer, although there may be exceptions peculiar to the custom and practice of a particular industry. However, an employer cannot force an employee to be searched unless it is expressly agreed to in the contract.

If an employer requests information about the conduct of other employees the employee may be under a duty to disclose information about conduct that falls within the range of the employee’s work activities. An employee who exercises managerial or supervisory functions may be obliged to disclose information to the employer, even if not asked, about the misconduct of other employees. So if an employee becomes aware of another employee’s damage to or theft of the employer's property, he or she must pass that information on to the employer.

While the courts are reluctant to intrude on an employee's spare time (that is, after knock-off time or prior to starting time), they have held that activities that are harmful to the employer's business (such as running a competitive business) may be incompatible with the duty to the employer. Basically, a worker should not tell others any details of the employer's profits or losses, customers, special methods or techniques used, or any information about the business that might help a competitor. Such insider knowledge is different from any skills, expertise, or general knowledge learnt or developed in the course of employment.

Some contracts of employment contain an express term preventing the employee, on leaving the employment, from entering into competition with the employer's business (restraint of trade clause). Such a term may be declared void by the courts despite this express agreement, unless it can be shown to be reasonable and not contrary to the public interest.

It is not a breach of the duty for an employee to disclose misconduct by the employer or other events that have occurred in the employment which ought to be disclosed in the public interest but, in so doing, the employee cannot also disclose the employer's trade secrets or misuse confidential information acquired in the employment. Under the Public Interest Disclosure Act 2018 (SA) (formerly the Whistleblowers Protection Act 1993 (SA)), some people who disclose information in the public interest have protection from victimisation resulting from the disclosure, although legal advice should be sought before disclosure [see ss 5 and 9]. In the case of Sutton v State of South Australia (1996) 68 SASR 13 the Supreme Court held that even the Ombudsman could be sued in the unlikely event that he or she victimised anyone for making an appropriate disclosure of public interest information. Public interest information is very broadly defined, and includes information that can be considered to be environmental and health information, or public administration information [see s 4]. An informant who is victimised can take legal action in the courts or can lodge a complaint with the Commissioner for Equal Opportunity, see discrimination.

If in the course of employment an employee creates or invents something when he or she is employed to do things of that sort, the property in the creation or invention (unless otherwise agreed) belongs to the employer, see copyright.

In some workplaces there are specific rules (often referred to as the employer’s policies) which may be handed to workers when they start their employment or sometimes they are displayed on notice boards. If before the employment contract is made the worker is given a copy of the rules and made to sign for them, or if the existence of the rules is reasonably brought to the worker's knowledge, the rules become part of the terms of the employment. If they are shown to the worker after the commencement of employment, he or she must consent to them before they become part of the contract.