The city command and control center (C4) can be considered as the heart of a smart city. In this sense, the big picture is that the C4 integrates local urban services and teams to make the city run smoothly and efficiently for residents, businesses, and visitors, guaranteeing people’s safety and security, by providing prompt responses to risks and occurrences (unexpected or expected). To achieve this, three major roles need to be well covered by C4: to identify risks and problems; to integrate planning and operations; and to communicate with citizens and city teams. Big events in venues—or having urban open spaces as venues—gather in specific regions more people, risks and, consequently, more complexities, forcing the C4 to adapt its operational arrangement to deal with these temporary scenarios. Based on Rio de Janeiro’s experiences such as the annual carnival parades and the 2016 Olympic Games, this chapter aims to highlight lessons learned and best practices regarding city command and control for big events as key element to deliver, as results, higher levels of city operational governance for events and minimizing its impacts in citizens’ daily routines. The topics covered includes communication strategies with citizens and operational teams; integrated operational planning within the C4; real-time monitoring; risks and contingencies assessments, via exercises; and rearrangement of C4 for street events. Authors utilized participant observation as methodology to develop this chapter, as they gathered information from direct participation in the working processes in Rio, and organized it in knowledge that can be used as reference for Sure project and other cities’ initiatives worldwide