Sports-based interventions are utilized today in many countries in cross-sectoral cooperation, for instance, as a means of social inclusion. However, not enough is known about the conditions of development or the formalization of operations. Accordingly, in this article, we focus on two instances of midnight football carried out in two suburban areas in Sweden in order to explore the mechanisms and conditions for interventions to achieve increased formalization and sustained operation. Through an analysis of interviews and network visualizations, we examine how collaborating agencies conceive of and describe their role in the assemblages of agencies surrounding and enabling the interventions. By looking closely at the forms of collaboration and communication in these networks, we find that the interventions have developed locally and not according to a central or strategic design. We identify three levels of design within the interventions, where communication, cooperation, and formalization can be governed: practice, program, and preconditions. Through a detailed analysis of these levels of intervention, we present crucial mechanisms for increased formalization and sustained operation and how these mechanisms differ between sites. In conclusion, on the basis of our analysis, we discuss refined approaches to understanding the temporality and interchangeability in the formation of cooperation and thus offer a refined conceptualization of the formalization of operations.