There are no laws at the moment to protect gay and lesbian people from discrimination, though new laws came into force in December 2003 making discrimination at work because of sexual orientation illegal.
At work, your employer may have their own equal opportunities policy which covers discrimination against gay and lesbian people. If they do, and they don't follow it, they could be breaking your contract of employment, and you could bring a claim either through an employment tribunal, or through the courts.
If you have HIV or AIDS, you may also face discrimination because of this. Someone living with HIV or AIDS (whether they are gay or not) may have protection under the Disability Discrimination Act. See the Community Legal Service leaflet 'Rights for people with disabilities' for more information about this.
People who have had 'gender reassignment' (often called a sex change) do have some legal protection against discrimination. The Sex Discrimination Act was changed in 1999 to protect 'transgendered' people against discrimination in employment and work training. But these regulations don't cover housing, education or services.
The regulations cover anyone who is about to go through, is going through, or has gone through gender reassignment. If you are discriminated against because of one of these, you will have a claim under the Sex Discrimination Act. Apart from avoiding discrimination in recruitment, dismissal and so on, your employer should allow you time off work for necessary medical treatment just as they would allow time off for other kinds of necessary medical treatment. They should also take action if you are harassed by other employees because of your gender reassignment.
The procedure for taking a case is the same as for any other Sex Discrimination Act claim (see 'What you can do about discrimination' ).
The Equal Opportunities Commission has a guide 'Sex Equality and Transexualism', which deals, in detail, with this kind of discrimination, including examples of case decisions which may help you.