Integrated impact assessment (IIA) is a prospective analytical tool intended to support governmental decision-making processes.
This fourth note in a series of 6 presents how the practice of IIA has been institutionalized in the United Kingdom. It describes its history, objectives, procedures and the tools used. In addition, the evaluation of the practice is discussed. Particular attention is also focused on the manner in which impact assessments with a single focus were included in the integrated analysis.