The Core Skills Project has developed in the "core skills" an instrument that can be used in the analysis of occupational competence. Any development of accreditation of work-based learning entails assessment of learning in the workplace. The success of such assessment depends on identifying the outcomes of experience in terms of competence and the work role of the learner. A linkage needs to be found between the raw observation or measurement of the individual events of a learner's program and the eventual interpretation of a certificate plus supporting evidence. The means chosen by the Core Skills Project has been to describe skills used in any situation in a way that could be related to any other. The core skills have been defined as being common to a wide variety of tasks and essential to carrying out those tasks. They are particularly important in helping to deal with two of the problems involved in using the workplace as a source of assessment information--difficulty of generalization and inequality of opportunity. The analytical and descriptive capacity of the core skills enables the significant workplace element within the Youth Training Scheme to be part of a coherent accreditation system. (YLB)