For those people who have the cognitive and social impairments described as a learning disability, personal choice is more often than not a limited experience, (Mencap, 1989). Simple choices may be usurped by the preferences of carers, and more serious decisions may be correctly or incorrectly deemed beyond their capacity. We will address two questions which repeatedly face clinicians working with adults with learning disabilities. First, how do we ascertain a person's level of competence to give consent in relation to medical treatment? Second, in the case where a person with learning disability is considered unable to give informed consent to treatment, how do we proceed to make a decision regarding treatment?