Chapter 03 · Reporting & strategyStrategy, Targets & Performance Management
Backcasting
Definition
A planning approach in which a successful future outcome is first imagined, and the question then asked: "what do we need to do today to reach that outcome?" In contrast to forecasting, which projects current trends forward, backcasting defines the endpoint — such as a fully sustainable state or a net-zero target — and derives the pathway backwards from it.
References
Definition vs forecasting; role in strategic sustainable development; The Natural Step's ABCD method based on backcasting from sustainability principles.
Overview
What it means
Backcasting is central to strategic sustainable development because incremental forecasting tends to project today's problems into the future and narrows options to marginal improvements. The Natural Step's framework for strategic sustainable development embeds backcasting from science-based sustainability principles in its ABCD method.
Normative climate scenarios (such as the IEA's Net Zero Emissions scenario) apply the same logic: define the 1. 5°C-consistent endpoint and derive required milestones.
How it is used
Organisations use backcasting for visioning, target-setting and transition planning: set the long-term goal, identify milestones, then plan actions and monitor against the pathway. It is common in municipal sustainability planning, corporate target-setting and national decarbonisation strategies.
Why it matters
Backcasting legitimises ambition: it starts from what is necessary (e. g. climate stability) rather than what currently seems feasible, exposing the gap between trends and goals — the conceptual basis of "ambition gap" analysis.