Scenario Descriptions

The GSG scenarios are based on a two-tier hierarchy. Conventional Worlds, Barbarization and Great Transitions represent fundamentally different social visions. Within each of these classes, a range of variants is considered. The GSG’s analysis has focused on the six scenarios described below. For more details, see Great Transition: The Promise and Lure of the Times Ahead.

Conventional Worlds

Conventional Worlds envision the global system of the twenty-first century evolving without major surprises, sharp discontinuities or fundamental transformations in the basis for human civilization. Dominant values and institutions shape the future, the world economy grows rapidly and developing countries gradually converge toward the norms set by highly industrial countries. Conventional Worlds scenarios are the subject of Bending the Curve.

Market Forces

This variant incorporates mid-range population and development projections, and typical technological change assumptions. The problem of resolving the social and environmental stress arising from global population and economic growth is left to the self-correcting logic of competitive markets.

Policy Reform

Policy Reform adds strong, comprehensive and coordinated government action, as called for in many policy-oriented discussions of sustainability, to achieve greater social equity and environmental protection. The political will evolves for strengthening management systems and rapidly diffusing environmentally-friendly technology, in the context of proactive pursuit of sustainability as a strategic priority.


These scenarios envision the grim possibility that the social, economic and moral underpinnings of civilization deteriorate, as emerging problems overwhelm the coping capacity of both markets and policy reforms. Barbarization scenarios are described in detail in Branch Points.


In this variant, crises combine and spin out of control, leading to unbridled conflict, institutional disintegration and economic collapse.

Fortress World

Fortress World features an authoritarian response to the threat of breakdown. Ensconced in protected enclaves, elites safeguard their privilege by controlling an impoverished majority and managing critical natural resources, while outside the fortress there is repression, environmental destruction and misery.

Great Transitions

Great Transitions explore visionary solutions to the sustainability challenge, including new socioeconomic arrangements and fundamental changes in values. They depict a transition to a society that preserves natural systems, provides high levels of welfare through material sufficiency and equitable distribution, and enjoys a strong sense of social solidarity. Population levels are stabilized at moderate levels and material flows through the economy are radically reduced through lower consumerism and massive use of green technologies.

The Eco-Communalism variant incorporates the green vision of bio-regionalism, localism, face-to-face democracy, small technology and economic autarky.
New Sustainability Paradigm
This variant shares some of the goals of the Eco-Communalism scenarios, but would seek to change the character of the urban, industrial situation rather than to replace it, to build a more humane and equitable global civilization rather than retreat into localism. The New Sustainability Paradigm is the focus of Great Transition.