Employers signal difficulties in sourcing technically-educated staff. They often engage, though to a limited degree, in cooperation with vocational schools to mitigate this difficulty. One of the reasons for the limited involvement of enterprises in cooperation with schools is the difficulty in assessing the benefits that it may bring. The aim of the study in the article was to develop and initially verify a model for evaluating the results of supporting secondary technical schools by manufacturing enterprises. The article features a multiple case study using several types of interviews, a distributed questionnaire and an analysis of secondary sources. The study was conducted in cooperation with four large manufacturing enterprises. The result of the research is a more thorough understanding of the possibilities and limitations in evaluating the results of support for schools. This support should translate in enterprises into more effective and efficient management of the competences of the future.