Typically, complex systems are operated by teams because of the diverse nature of the tasks and the need for specialized backgrounds. Test beds called “scaled worlds” or “microworlds” have been developed that simulate the team task and facilitate research on teams. The use of microworlds to simulate aspects of real work in a laboratory setting is increasingly bridging the gap between the uncontrolled field study and the artificial control of the traditional psychological laboratory. The capabilities to script scenarios, manipulate variables, and collect data through embedded measurement are all typical features of microworlds. In this chapter we highlight considerations for selecting or designing a microworld and collecting data within it. We also provide some examples of microworlds and point to other applications of this technology for training exercises and technology evaluation.