The Contracting States agree to review periodically the structure of technical and vocational education, study programmes, plans, training methods and materials, as well as forms of co-operation between the school system and the world of work, so as to ensure that they are constantly adapted to scientific and technological progress, to cultural progress and to changing employment needs in the various sectors of the economy, and that advances in educational research and innovation are taken into account with a view to application of the most effective teaching methods.