Sustainability reporting assurance.

This chapter addresses the assurance service for corporate sustainability information. First, the main reasons and benefits of sustainability assurance are discussed, as well as some key concepts such as the difference between mandatory and voluntary assurance, the levels of assurance, the ethical and professional requisites of the experts providing this service, the applicable standards, the subject matter and the preconditions of an assurance service engagement. An analysis of the crucial engagement planning and performing phases follows, with a particular focus on staffing the engagement, determining materiality, and obtaining evidence. The typologies, contents and goals of assurance documentation are also described, as well as the contents of the assurance report and possible conclusions. The chapter ends with some remarks on the criticalities characterising the assurance service of sustainability reports.