The Magenta Book: Central Government Guidance on evaluation

Author HM Treasury

The Magenta Book, updated in 2020 by the HM Treasury, is essential reading for local authorities, and other relevant place-stakeholders, applying for funding and creating business cases. It focuses on how to evaluate impacts, processes, and projects. Used alongside complementary resources, such as the Aqua Book and Green Book, it helps with the development of transparent, objective, evidence-based appraisal and evaluation of proposals, to inform decision making and business cases. It can also help place stakeholders to evaluate the effectiveness and impacts of any place interventions.

Date added 26 October 2020
Last updated 26 October 2020

This 2020 update of the HM Treasury’s Magenta Book is essential reading for local authorities, and other relevant place-stakeholders, applying for funding. It can also help place stakeholders to evaluate the effectiveness and impacts of any place interventions. The guide focuses on how to evaluate impacts, processes, and projects, which involves “a systematic assessment of the design, implementation and outcomes of an intervention” (p. 5), and enables learning from, and accountability for, interventions. Understanding more about evaluation is important since “understanding the efficiency and effectiveness of interventions and their impacts is critical to effective decision-making” (p.3). As the guide further explains, evaluation can help to answer questions such as: is the intervention working as intended? Does it benefit different groups in different ways? How can the policy be improved? Does it provide value-for-money? The Magenta Book covers the following key topics: what evaluation is; why, how and when to evaluate; designing an evaluation; appropriate evaluation methods and the use of data; managing an evaluation; and using and disseminating evaluation findings. Used alongside complementary resources, such as the Aqua Book, Green Book, and Managing Public Money Guide, it helps with the development of transparent, objective, evidence-based appraisal and evaluation of proposals to inform decision making and business cases.