The neo-liberal shift in the Swedish welfare system has entailed different types of power regimes operating through human bodies – through constant processes of surveillance and discipline, including measurement and documentation. In this chapter, we discuss two such areas of social work in a Swedish context. First, a general discussion of institutional changes and their implications for social work through the implementation of New Public Management and Evidence-Based Practice. Second, through a particular practice, namely the shift in treatment of people who are addicted to opiates, from being a social treatment to becoming medicalized and biochemical treatment.