With the investment of large sums of money in new technologies forschools and education authorities and the subsequent training of teachers to integrate Information and Communications Technology (ICT) into their teaching strategies, it is remarkable that the old outdated models of assessment still remain. This article highlights the current problems associated with pen-and paper-testing and offers suggestions for an innovative and new approach to assessment for the twenty-first century. Based on the principle of the 'wise examiner' a computerised adaptive testing system which measures pupils' ability against the levels of the United Kingdom National Curriculum has been developed for use in mathematics. Using constructed response items, pupils are administered a test tailored to their ability with a reliability index of 0.99. Since the software administers maximally informative questions matched to each pupil's current ability estimate, no two pupils will receive the same set of items in the same order therefore removing opportunities for plagarism and teaching to the test. All marking is automated and a journal recording the outcome of the test and highlighting the areas of difficulty for each pupil is available for printing by the teacher. The current prototype of the system can be used on a school's network however the authors envisage a day when Examination Boards or the Qualifications and Assessment Authority (QCA) will administer Government tests from a central server to all United Kingdom schools or testing centres. Results will be issued at the time of testing and opportunities for resits will become more widespr