Urban Dynamics

Forrester applied the system dynamics method developed at MIT to a city. The model treats an urban area as a closed system of stocks and feedback loops linking population, housing and industry, simulates a city through growth, maturity and decline over long periods, and then tests the proposed remedies of the day against it. Many of the results ran against accepted policy, which made the book controversial and started a research programme that reached into government urban policy.

It is the first whole-city computer model and the one most later efforts react to. A twin builder will find in it the discipline of stating a system's boundary, stocks and rates explicitly, the habit of testing policies inside the model before outside it, and a clear example of how a model's assumptions decide its conclusions.