Ideas derived from social simulation models can directly inform the design of distributed computer systems. This is particularly the case when systems are “open”, in the sense of having no centralised control, where traditional design approaches struggle. In this chapter, we indicate the key features of social simulation work that are valuable for distributed systems design. We also discuss the differences between social and biological models in this respect. We give examples of socially inspired systems from the currently active area of peer-to-peer systems, and finally we discuss open areas for future research in the field.