This chapter investigates how healthcare experts engage in the development of Automated Decision Making (ADM), and how their discretionary work unfolds through the participation in designing ADM applications in different use contexts. Drawing on semi-structured interviews, the chapter theorises discretionary work by showing how institutionalised demands for accountability and accuracy forge the healthcare experts’ delegation of decisions using algorithms. Contrary to research claiming that ADM is about to outperform healthcare experts and make the need for clinical reasoning dispensable, the study shows that the introduction of ADM raises new demands for expertise and human accountability, whereby ADM is integrated into an existing professional practice of exploration. © 2022 selection and editorial matter, Sarah Pink, Martin Berg, Deborah Lupton, Minna Ruckenstein.