手法を比較

	Scenario Planning for Policy	Ex-Ante Policy Appraisal
分野	Public Policy	Public Policy
系統	Process / pipeline	Process / pipeline
提唱年	1991	2022
提唱者	Pierre Wack & the Royal Dutch/Shell school; popularised by Peter Schwartz	Public-finance appraisal tradition; codified by HM Treasury (Green Book)
種類	Qualitative strategic-foresight method	Structured ex-ante appraisal of policy options
原典	Schwartz, P. (1991). The Art of the Long View: Planning for the Future in an Uncertain World. New York: Doubleday/Currency. ISBN: 9780385267311	HM Treasury (2022). The Green Book: Central Government Guidance on Appraisal and Evaluation. London: HM Treasury.
別名	Scenario Planning, Intuitive Logics Scenarios, Policy Scenario Planning, Strategic Foresight Scenarios	Policy Appraisal, Options Appraisal, Green Book Appraisal
関連	4	4
概要	Scenario planning is a strategic-foresight method that develops a small set of plausible, internally consistent and divergent stories about how the future might unfold, in order to test policies and strategies against deep uncertainty. Rooted in the work of Pierre Wack at Royal Dutch/Shell and popularised by Peter Schwartz's The Art of the Long View, it does not try to predict the future but to expand decision-makers' thinking about it. By exploring several qualitatively different futures, policymakers can craft strategies that are robust across a range of possibilities rather than optimised for a single forecast that may not arrive.	Ex-ante policy appraisal is the structured assessment of the costs, benefits, risks and trade-offs of alternative options for achieving a policy objective, carried out before a decision is taken. Codified in guidance such as the UK Treasury's Green Book, it provides a disciplined framework for deciding whether to intervene and, if so, how — by establishing the rationale and objectives, generating and narrowing a range of options, appraising each against a counterfactual, and recommending the option that offers best value for public money. Appraisal is the forward-looking complement to ex-post evaluation, which judges interventions after they have run.