Laws banning age discrimination in the workplace come into effect on 1 October 2006.
It is the latest type of discrimination to be tackled after race and sex discrimination.
The government wants people to have the right to work longer, particularly as we are living longer, healthier lives.
But it is worried that the ageist attitudes of some employers are stopping people from doing this.
Defining age discrimination
This is when an employee is discriminated against by an employer on the grounds of age.
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Discrimination takes different forms.
There is overt discrimination - for example, someone being made redundant because they are considered too old for the job.
And there is indirect discrimination, such as making ageist comments.
The extent of the problem
Unions cite age as the most common form of discrimination in the workplace.
However, age discrimination has not had the high profile of discrimination on grounds of sex or race, both of which have been outlawed for many years.
In some industries, such as media and advertising, age discrimination has been endemic, an almost accepted fact of life for decades.
How the law works
It will be unlawful to discriminate against an employee under the age of 65 on the grounds of age.
The anti-discrimination law covers a range of workplace issues.
Employers will not be able to specify that a new recruit should be above or below a particular age.
In addition, employers who fire workers or deny them the same training opportunities as their colleagues on age grounds will be in breach of the law.
But there are get-out clauses. If the employer can 'objectively show' a sound business reason for discrimination then it may be permitted.
And the law does not apply to workers over the age of 65, where they merely have the right to request an extension of their working lives.
Discrimination outside the workplace, for example in providing goods and services, is not covered.