If you are a Solicitor, qualified legal practitioner from another relevant jurisdiction or an academic wishing to transfer to the Bar, you will need to apply to the Bar Standards Board in the first instance. Depending on your experience and qualifications, they will send you a letter detailing their decision with the conditions you must fulfil in order to be called to the Bar.
Once you have received your letter from the Bar Standards Board, you may apply to join an Inn. You must be a member of an Inn to be called to the Bar.