While acknowledging that a system of vocational qualifications might be perceived as having any number of possible purposes, this paper identifies three primary functions that any vocational qualification must fulfil by dint of being a vocational qualification. It is argued that current arrangements are unable to fulfil these essential functions due to certain intrinsic and irremediable conceptual difficulties with the National and Scottish Vocational Qualification (N/SVQ) system. The practical implications of this are illustrated through an account of little documented events in the 1990s when many of the UK's major companies found it necessary to abandon the UK's system of N/SVQs in favour of an alternative system precisely because of concerns that the N/SVQ did not fulfil the functions required of a vocational qualification. Of particular significance is an apparent inconsistency between the N/SVQ system and health and safety law: the so-called "competence" assessment procedures of the N/SVQ being seen to be methodological at odds with the legal requirements for competence.