Neighborhood change is a complex process. Much has been written in a general way about what happens. Very little has been written about why. This report represents the findings of a project whose charter was to explain neighborhood evolution and decline i~ terms of the behavior of the actors causing it. We wanted to understand why people do what they do, and how their actions cause change over time.

Our explanation takes the form of a computer model. Different parts of the model simulate the behavior of different actors households, individuals, landlords, homeowners, builders, employers, school superintendents, zoning board members. Each year the model predicts what these people will do and accumulates the results of their individual actions, thereby simulating aggregate change in neighborhoods.

This report is part of the collection of scanned historical documents available to the public.