the following participated in preparing this monograph: for Ancifap (IFAP-IRI): Director of the project and editor of the text: Nicola Fressura ; with the assistance of Marina Sampietro ; for ISFOL: supervisor of evaluative elements: Alfredo Tamborlini, updating of statistics: Augusto Ruberto ; on behalf of CEDEFOP-European Centre for the Development of Vocational Training, 1995, project coordinators: J. Michael Adams, F. Alan Clarke ; under the responsibility of:Corrado Politi. -- First ed.. -- European Centre for the Development of Vocational Training.