Systems dynamics and agent-based models are used here to examine the spread of fixed line phones in Britain over 120 years. Both models approximately fit the data and it is shown that in this case the two approaches can be used to complement each other. The SD model is simpler and produces a better fit while its deterministic nature facilitates sensitivity analysis. The agent-based model provides greater explanatory power, which can in turn be used to fine tune the systems dynamics model. Together, they can be combined to tell a plausible story about the adoption of telephones.