Background After completing university education, biomedical laboratory scientists work in clinical laboratories, in biomedical research laboratories, in biotech, and in pharmaceutical companies. Laboratory diagnostics have undergone rapid development over the recent years, with the pace showing no signs of abatement. This rapid development challenges the competence of the staff and will most certainly influence the education of future staff. This study aimed to examine what was considered the necessary competencies needed to pursue a career as a biomedical laboratory scientist. Methods A modified Delphi technique was used, with the panel of experts expressing their views in a series of three questionnaire. Consensus was defined as the point which 75 % or more of the panel participants agreed that a particular competency was necessary. Results The study highlights the perceived importance of mostly generic competencies that relate to quality, quality assurance, and accuracy, as well as different aspects of safety, respect, trustworthiness (towards patients/clients and colleagues), and communication skills. The results also stress the significance of self-awareness and professionality. Conclusions We identified important competencies for biomedical laboratory scientists. Together with complementary information from other sources, i.e., guidelines, laws, and scientific publications, the competencies identified can be used as learning outcomes in a competency-based education to provide students with all the competencies needed to work as professional biomedical laboratory scientists.