The 1970s Plan to Save Our Cities with Computer Models
Imagine it's the early 1970s. Environmental movements are sweeping across North America, concerns about pollution and urban sprawl are mounting, and confidence in established political and scientific authority is eroding. Against this backdrop of social and ecological anxiety, an ambitious group of ecologists, urban planners, and systems scientists embarked on a radical mission: to build a computer simulator that could predict the future of cities. This was the Inter-Institutional Policy Simulator (IIPS) project—a four-year endeavor between 1970 and 1974 that aimed to create a technological crystal ball for urban planning 1 .
The project's goal was both revolutionary and pragmatic: to create a computer-based simulation model that would allow planners—and even laypeople—to test the potential consequences of different policies before implementing them in the real world 1 .
The IIPS project emerged at a critical historical juncture, when the limits of traditional planning were becoming apparent. Cities were increasingly understood not as mere collections of buildings and people, but as complex socio-ecological systems where human decisions interacted with environmental processes in ways that were difficult to predict or manage 2 . Though the project ultimately failed to create a working simulator for Vancouver, its ambitious attempt to bridge ecology, planning, and computer science offers valuable insights for today's challenges in urban sustainability and resilience.
IIPS project launched with interdisciplinary collaboration
Development of theoretical frameworks and component models
Project concluded without achieving fully functional simulator
To understand the ambition of the IIPS project, one must first grasp the theoretical revolution that made it possible. The project stood at the intersection of three emerging fields: systems ecology, urban planning, and computer science. Each contributed essential concepts to this daring endeavor.
The intellectual foundation of IIPS came from systems ecology, which emerged during the Cold War with a focus on computer simulation and mathematical models of natural environments 1 . This approach viewed ecosystems as complex adaptive systems—networks of interacting components that together produce emergent behaviors that cannot be predicted by studying individual parts in isolation 3 .
The crucial innovation of IIPS was extending this perspective from natural ecosystems to human settlements, conceptualizing cities as integrated "socio-ecological systems" where social and biophysical agents interact across multiple scales 2 3 .
The theoretical framework of IIPS translated into a specific methodological approach centered on computer simulation. The project aimed to create what its developers called the "Inter-Institutional Policy Simulator"—a computer-based model that would simulate the urban dynamics of Vancouver, British Columbia 1 .
The methodology reflected the systems thinking prevalent in the project. Just as the city was understood as an interconnected whole, the simulator was designed to capture the feedback loops and cross-scale dynamics that characterized urban development 2 .
Provided framework for understanding complex interactions
Enabled simulation of urban dynamics
Applied insights to practical city development
While the IIPS project developed broad theoretical frameworks, its most concrete application was an ambitious attempt to model the urban dynamics of Vancouver, British Columbia. This case study represents a crucial "key experiment" within the larger project—an effort to translate abstract systems theory into a practical planning tool for a real city.
The Vancouver implementation followed a methodology characteristic of the systems approach to complex problems. Rather than attempting to build a complete city model all at once, the team pursued what might be called a modular strategy, developing component models that represented different aspects of the urban system 1 .
Despite four years of work and substantial institutional support, the IIPS project failed to create a functioning policy simulator for Vancouver. The analysis of this outcome reveals much about the challenges of modeling complex social-ecological systems:
| Challenge Category | Specific Limitations | Impact on Project |
|---|---|---|
| Technical Barriers | Limited computing power, data processing capabilities | Restricted model complexity and accuracy |
| Theoretical Gaps | Incomplete understanding of social-ecological feedbacks | Difficulty capturing dynamic interactions |
| Methodological Issues | Tension between "IIPS as Platform" and "IIPS as Product" | Divergent priorities among collaborators 1 |
| Institutional Constraints | Coordination challenges between multiple institutions | Slowed development and implementation |
The Vancouver experiment revealed a fundamental tension between theoretical ambition and practical implementation 1 .
The project demonstrated that understanding cities requires interdisciplinary collaboration that bridges natural and social sciences.
The ambitious goal of simulating an entire city required developing what we might now call a "scientist's toolkit"—a collection of conceptual frameworks, technical resources, and methodological approaches that together would enable the modeling of urban dynamics. Though the specific technical implementations have been surpassed by modern computing, the conceptual toolkit developed for IIPS remains remarkably relevant.
| Component Category | Specific Elements | Function in Research |
|---|---|---|
| Theoretical Frameworks | Systems ecology, Complex adaptive systems theory | Provided conceptual foundation for understanding cities as integrated wholes 1 3 |
| Modeling Approaches | Computer simulation, Mathematical models | Enabled representation of urban dynamics and testing of policy scenarios 1 |
| Data Resources | Demographic records, Environmental data, Economic statistics | Provided empirical foundation for model parameterization and validation |
| Interdisciplinary Teams | Ecologists, Urban planners, Computer scientists | Brought diverse expertise to address different aspects of urban complexity 1 |
| Participatory Methods | Public programs, Educational events | Engaged community members in planning processes 1 |
At the heart of the IIPS methodology was what contemporary scholars would call a transdisciplinary approach—one that not only bridged scientific disciplines but also engaged with community stakeholders and policymakers 1 .
This reflected a growing recognition that addressing complex urban challenges required integrating diverse forms of knowledge, from specialized expertise to local understanding of place.
The project also pioneered the use of boundary objects—concepts or frameworks that facilitate communication and collaboration across different disciplines or social worlds.
The notion of "systems" itself functioned this way within IIPS, providing a shared vocabulary and conceptual space where ecologists, planners, and computer scientists could work together despite their different disciplinary backgrounds 2 .
Though the Inter-Institutional Policy Simulator project failed to achieve its primary goal of creating a functioning urban simulator, its legacy has proven surprisingly durable and relevant to contemporary planning and systems science.
One of the most important insights from examining IIPS is the distinction that historians have drawn between "IIPS the Product" (the simulator itself) and "IIPS the Platform" (the network of experts and institutions that collaborated on the project) 1 . While the product never materialized as envisioned, the platform had lasting effects:
IIPS helped establish new ways of organizing research across disciplinary boundaries, prefiguring contemporary interdisciplinary research centers focused on sustainability 3 .
The project contributed to the development of social-ecological systems theory, which has become a dominant framework in sustainability science 3 .
The challenges encountered in IIPS led to more sophisticated approaches to modeling complex systems, acknowledging limitations while building on insights.
Perhaps most significantly, IIPS represented an early attempt to reimagine the relationship between technoscience and the public in an era of environmental anxiety and social transformation 1 .
The story of IIPS offers valuable lessons for current efforts to create sustainable, resilient cities in the face of climate change and rapid urbanization:
Today, as cities worldwide grapple with the intersecting challenges of climate change, inequality, and sustainable development, the vision that animated IIPS—of holistic, evidence-informed, and participatory urban planning—has never been more relevant.
While the specific computational approaches have evolved dramatically, the fundamental insight that cities are complex social-ecological systems continues to guide innovative research and practice in urban sustainability 3 .
Contemporary "digital twins" of cities build upon the foundational concepts pioneered by IIPS, using advanced computing to create dynamic urban models.
The Inter-Institutional Policy Simulator project of 1970-1974 represents a fascinating chapter in the history of urban planning, ecology, and computer science—a bold experiment that fell short of its ambitions but left an enduring intellectual legacy.
The project embodied the optimistic technoscientific spirit of its era while also reflecting the growing environmental consciousness that would permanently change how we think about human-nature relationships.
Though IIPS failed to create the comprehensive urban simulator it envisioned, it succeeded in demonstrating the power of systems thinking for understanding cities and their complex challenges.
The project helped pioneer an approach to urban planning that recognizes the interconnectedness of social and ecological processes, and that acknowledges the unintended consequences that can emerge from well-intentioned interventions.
As contemporary planners and policymakers increasingly turn to "digital twins" and other sophisticated computational models to guide urban development, the story of IIPS serves as both inspiration and caution. It reminds us of the transformative potential of interdisciplinary collaboration while warning against technological solutionism that underestimates the complexity of social-ecological systems. The dream of simulating cities continues to evolve, but it still bears the imprint of those early pioneers who first attempted to model the nature of cities nearly half a century ago.