The Act brings together nine existing pieces of discrimination legislation into one single Act.

The same characteristics that were protected by existing discrimination legislation (age, disability, gender reassignment, race, religion or belief, sexual orientation, marriage and civil partnership, pregnancy and maternity) are now known as "protected characteristics".

The Act extends discrimination law in line with case law to cover both associative discrimination (direct discrimination against someone because they associated with someone who has a protected characteristic); and perceptive discrimination (direct discrimination against someone because others think they have a particular protected characteristic).

Disability discrimination is extended to include discrimination "arising from" a disability for example, treating someone with dyslexia unfavourably because of their tendency to make spelling mistakes. Indirect discrimination has also been extended to cover disabled people. Employers may no longer ask questions about job applicants’ health before making a job offer, except in five limited circumstances.

These are where the questions are necessary to:

l discover whether reasonable adjustments have to be made to the selection process

l decide whether an applicant can carry out a function that is essential to the job

l monitor diversity among applicants

l take positive action to help a disabled person where that is allowed by other provisions

l check that the candidate actually has a particular disability genuinely required by the job provided that requirement is a "proportionate means of achieving a legitimate aim".

ACAS has advised: "From October employers should no longer send out pre-health questionnaires with employment application packs."

Transsexuals no longer have to be under medical supervision to be protected.

A person bringing an equal pay claim can now rely on a hypothetical comparator (also see below). Previously a claimant had to compare him/herself against someone of the opposite sex doing equal work in the organisation.

Employers cannot prevent their employees from discussing whether there are differences in their pay related to a protected characteristic.

"Gagging clauses" in employment contracts are now banned.