Discrimination in employment has been prohibited by an International Labour Organisation (ILO) treaty, Convention 111, since 1958.
Taking a lead from the ILO, most developed countries have laws protecting employees from workplace discrimination or bias, largely to ensure that workers are not hired or fired because of their sex, age, race, disability, nationality, family or marital status or sexual orientation, among other things.
Workplace sexual harassment is also considered in many places to be a form of workplace discrimination.
Not all societies have laws protecting employees from all of the above. These laws are often enforced by government bodies.
In Hong Kong, for instance, four separate ordinances guarantee employees legal protection from being discriminated against on the basis of their race, gender, disability and family status.
The laws are enforced by the Equal Opportunities Commission, a statutory agency which investigates cases and mediates disputes to help parties reach a settlement.
If mediation fails, it can help complainants to go to court.
The United States too has a similar system. The US Equal Employment Opportunity Commission is a federal law enforcement agency that enforces laws against workplace discrimination.
It investigates complaints of workplace bias based on 10 different categories, including an individual's race, colour, national origin, religion, sex, age and disability among other things.
It can also mediate in disputes between employers and employees and file discrimination suits against employers on behalf of alleged victims.
The American system, which is known to dole out large sums of compensation to victims, has been criticised as being too expensive and for the fact that most discrimination cases are notoriously hard to prove.
However, a representative of the commission told The Sunday Times that the benefits of "protection and justice" for victims far outweighs the costs of the system.
While places like the US and Hong Kong combat workplace discrimination through their labour laws, others like Britain, Finland, Sweden and South Korea combat it through laws aimed at promoting equality and human rights.
In South Korea, discrimination complaints by employees are investigated and dealt with by the country's national human rights commission.
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