Regardless of the level of autonomy provided by the individual robots, teams of mobile robots will always require human command and control for tasking, monitoring, error remediation, and coordination. Multiple mobile robot systems are hard real-time multi-agent systems and are often employed in hazardous or inaccessible environments. Thus, it is necessary that human-robot interfaces (HRIs) be developed and tailored specifically to multiple mobile robot systems. These HRIs will be different from single-robot control interfaces because of the heterogeneity of the robots, the multi-tasking nature of the application, and the divided attention demands on the operator. In addition to the requisite command and control functions of the unit (e.g., a graphical user interface, communications network management, and sensor data acquisition channels), the HRI will require efficient multi-agent planning and tasking interfaces and a feedback display and execution monitoring system able to fuse diverse data. In this paper we will discuss the characteristics of multirobot HRIs and present data that should guide the design of such interfaces. In particular, we will discuss the design of multi-modal command/feedback interfaces, alert-driven presentation managers, and graphical user interfaces. Experiments and ongoing work from the DARPA Tactical Mobile Robot (TMR) program will be presented that indicate current progress in the design and implementation of such systems.