This chapter explores the metaphysics of systems of powers, which contain no qualities and have at least two powers in a dynamic relation. In order to account for the reality of higher-level properties in the macro world and everyday experience, whether they are powers or qualities, powers must work together. This chapter first delineates different kinds of multilevel systems of properties, specifying how powers and qualities might be related across different systems. Then, building on the idea of powers holism introduced in Chapter 6, this chapter characterizes what it means for powers to form a unified system. Next, the possibility of ontologically emergent properties, particularly qualities, appearing out of a system of powers, is explored. But this assumes that there are genuine qualities, whereas this chapter ultimately suggests that what appear to be genuine qualities are quasi-qualities.