This book is based on a corpus of audit reports from a large international company based in Italy. It takes a corpus-based approach to the analysis of the specialised language of internal audit reports, with an aim to informing non-native speakers interested in the auditing profession (where all audit reports in major companies are written in English) of the recurring features of this text type. As well as the language subtleties required in the writing of the reports, such as the skilful use of modal verbs for suggesting changes and the hedging required to avoid offence when presenting negative findings, the book also focuses on the interpersonal skills necessary in a good auditor, and the politeness strategies needed.