Compare methods

	Ex-Ante Policy Appraisal	Regulatory Impact Analysis
Field	Public Policy	Public Policy
Family	Process / pipeline	Process / pipeline
Year of origin	2022	1995
Originator	Public-finance appraisal tradition; codified by HM Treasury (Green Book)	Government regulatory-reform practice; standardised by the OECD
Type	Structured ex-ante appraisal of policy options	Systematic ex-ante appraisal of proposed regulation
Seminal source	HM Treasury (2022). The Green Book: Central Government Guidance on Appraisal and Evaluation. London: HM Treasury.	OECD (2020). Regulatory Impact Assessment, OECD Best Practice Principles for Regulatory Policy. Paris: OECD Publishing.
Aliases	Policy Appraisal, Options Appraisal, Green Book Appraisal	RIA, Regulatory Impact Assessment, Impact Assessment of Regulation
Related	4	4
Summary	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.	Regulatory impact analysis (RIA) is a systematic process for appraising the likely costs, benefits and effects of proposed regulation before it is adopted. Promoted by the OECD as a cornerstone of good regulatory governance, it requires governments to define the problem a regulation is meant to solve, set out alternative options including non-regulatory ones, assess the impacts of each against a do-nothing baseline, consult affected parties, and recommend the option that delivers the greatest net benefit. RIA aims to ensure that new rules are evidence-based, proportionate and justified rather than imposed without examination of their consequences.