The institution of the Post-Secondary Year - Apprenticeship Class was introduced in Greece in 2013 and after its pilot phase, its application in Vocational High Schools (EPAL) throughout the country was expanded in 2017. After the completion of four years of presence and implementation of the institution, with significant benefits for the apprentices, some factors emerge that make the participation and operation of the trainers involved in the Apprenticeship difficult. The aim of this study is to record, investigate and interpret a) the difficulties trainers encountered in their educational work and b) the necessary supplies they utilized to deal effectively with these difficulties. The sample was fifteen (15) trainers of EPAL who participated in the implementation of the Apprenticeship. The qualitative method was selected for the research, with semi-structured interviews as a tool for data collection and thematic analysis for their analysis. According to the findings of the research, trainers face difficulties in their educational work, mainly in the extensive course material, the low level of knowledge and the indifference of apprentices. The main means they use in the classroom to manage and deal with these difficulties are the very good knowledge of their specialized subject, the extensive educational experience, the application of the principles and practices of Adult Education and their skills. The present study aims to contribute, through the utilization of the research conclusions, to the feedback of education executives and trainers for the functional improvement and enhance the effectiveness of the institution.