The transition from school to vocational education and training (VET) is becoming more difficult for an increasing number of adolescents. Despite the growing significance of this phase, the- re is hardly any research regarding interventions targeting stu- dents’ resilience, especially with regard to their capacity to join the labour market. This paper aims at describing the research process of developing three different interventions in coopera- tion with a number of practitioners who teach in so-called in- terim solutions. The goal of the paper is, thus, to illustrate how design-based research (DBR) can be conducted in the context of vocational education. The comprehensive three-cycle develop- ment of three interventions with the aim of fostering students’ conflict management competence, attribution and self-efficacy will be used as a single case study to illustrate a complex DBR project. Each step in the design-research process will be reflec- ted, resulting in a discussion of the possibilities and obstacles of combining formative and summative evaluation in the DBR process.