Electronic measures and tools for testing competences meet increasing awareness in European education. There is some evidence that e-testing is no longer viewed as a mere means for automation of an existing process, but indeed reconceptualises it with desirable improvements and inevitable challenges. The underlying idea is that electronic testing could improve the effectiveness, i.e. improve identification of skills, and efficiency, by reducing costs (financial efforts, human resources etc.). When dealing with evaluation of skills, an obvious advantage of computer based assessments over the traditional pencil and paper is computer adaptive testing (CAT). CAT is often developed on the basis of item response theory (IRT) psychometric model family. An advantage of this approach is the reduction of test execution time, the test taker being always faced with a "realistic" challenge. Moreover, it is claimed as more secure, since each test taker is given a tailored test, and cheating becomes difficult. CAT is completely dependent on technology and as yet it cannot handle open-ended questions. The pool of items has to be quite large. Cost-benefit considerations aim at verifying the strengths and weaknesses, potentials and barriers posed in terms of their application in real situations. Any of the delivery modes, whether Paper-Pencil and/or computer-based, comprises advantages and challenges which can hardly be compared, especially in relation to estimated costs. The use of CBT includes additional benefits which can be achieved from a organisational, psychological, analytical and pedagogical perspective. Whereas the use of computers in the assessment of skills is increasingly common in the US, there are not many experiences at European level as far as large-scale assessments are concerned. Some small scaled experiences are reported at a project level, e.g.- DIALANG: The DIALANG project is about computer based language testing. It is an assessment system intended for language learners who want to obtain diagnostic information about their language proficiency, providing also advice about how to improve language skills. DIALANG is Internet based freeware, currently managing diagnostic tests in 14 different European languages. - TAO: The TAO (Test Assisté par Ordinateur) system is a modular platform for internet-based computer aided testing. The platform allows the management of knowledge pertaining to subjects (individuals whose competencies and knowledge may be assessed), groups of subjects, tests and items (elements of tests requiring an answer from the user). - PISA pilot studies: (additional national pilots 2003, CBAS 2006) - Literature review - Expert interviews - Case studies - Evaluation of platforms, tools and services Experiences are not sufficiently documented yet but results so far suggest that IT based tools could support the assessment process and the analysis of results. In terms of language skills assessment there are certain specific barriers to be taken into account. Whether undertaken in an electronic mode or not, the most important challenge of assessing productive skills is, in both cases, that heavy investments are needed to deliver and generate results at large-scale level. 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