For a person to call themself a "BSL/English interpreter", you should expect them to be skilled and professional. They should be registered with the National Register of BSL/English Interpreters and work within the national Code of Conduct and Guidelines of Professional Practice. Ideally, the person should also be registered with ASLI, the professional association for BSL/English Interpreters in England, Wales and Northern Ireland.

The National Registers for Communication Professionals working with Deaf and DeafBlind People (NRCPD) is the only national register of suitably trained BSL/English interpreters for England, Wales and Northern Ireland. There are various categories of membership, the highest being "Member of the Register of BSL/English Sign Language Interpreters" (MRSLI for short). NRCPD also has a complaints procedure in the unfortunate event that the deaf or hearing consumer has cause to complain.

The Association of Sign Language Interpreters (ASLI) two different levels of membership, the highest of which is "Full Member" of the Association of Sign Language Interpreters or "MASLI" for short. Full details of their Code of Professional Conduct can be found on their website.

Both organisations require their registered BSL/English interpreters to have obtained an Enhanced CRB check due the variety of situations and people that they will be required to work with.

As mentioned on the page marked "British Sign Language", the British Deaf Association currently estimate that there are around 250,000 deaf people in the UK who use BSL as their first or preferred language (this includes both people born deaf as well as those who became deaf at some later point in their life from early childhood onwards).

To meet this demand, there are currently around 320 MRSLI and around 150 Trainee/Junior Trainee interpreters throughout England, Wales and Northern Ireland.

For Greater London, based on a population of 7,000,000 people, conservative estimates suggest that there are a minimum of 7000 born-deaf people who use BSL as their first or preferred language (ie: this number increases when including those who became deaf at any later point in their lives and now use BSL as their first/preferred language). To meet this local demand, there are around 55 MRSLI and a further 20 Junior Trainee & Trainee interpreters registered with NRCPD in Greater London. That's just 75 people. Even looking more broadly, there are only around 80 registered MASLI and around 30 ASLI Associate member interpreters from across the whole of Greater London, Surrey, Kent and Sussex. So that's a total of 110 ASLI members to meet the need of over 7000 people in Greater London alone.

As you can imagine, this means there is a huge demand for their services so it is important to book an interpreter as far in advance as possible (eg: 4 - 6 weeks ahead or more), either directly or via a specialist BSL/English interpreting agency. Having mentioned this need for forward planning, it may be possible to book at shorter notice due to a prior booking having been cancelled etc. Sadly, this means that there are some other people who call themselves 'interpreter' but are not members of either/both of the above organisations. They are not governed by any Code of Conduct or a complaints procedure should they provide a poor service and their level of linguistic and interpreting ability is usually significantly below that of a suitably trained BSL/English interpreter. Similarly, there are some agencies who provide individuals who may not have the necessary skill or training. With this in mind, there is an Agency Steering Group whose member agencies are committed to upholding high standards. Please see the links page for their web site to find out more information about them.

Similarly, a BSL/English interpreter is sometimes incorrectly called a "Signer". This term is more often used to describe people who are learning to become BSL/English interpreters. These people are likely to have less fluency with BSL than interpreters and have often not yet been taught the necessary processes involved in effective interpreting. In addition to calling themselves a "Signer" these people are sometimes called Communication Support Worker or Communicator.