This survey investigates four different areas, all of which are relevant in the context of searching and securing an area using UGVs. The first area is that of coordinating the searchers, so that a region of interest is completely searched and an intruder cannot sneak into sectors that are already covered. The second is flocking and formation control, i.e., how to design control laws for each agent so that the group as a whole converges to some desired relative positions and can be moved as a unit. This is useful for transporting a group of UGVs to and from the search region. The third area is how to coordinate agents performing a task, so that they maintain inter-agent communication. This is a requirement for fully benefitting from using multiple robots. Finally, we also study how to move agents such that they maintain a line of sight between them, which is useful for detection. The conclusion is that there are complete algorithms for searching an area that has no obstacles, but more realistic environments are less studied. For flocking and formation control there are many useful algorithms and perhaps the most important design choice is to select between those using local communication and those that are centralized. For maintaining inter-agent communications, the most robust methods employ dedicated relaying agents and/or protocols that are disruption-tolerant. For maintaining a line of sight, the most reliable methods use hard geometric constraints for what points are feasible to go to.