This document sets out our company monitoring framework for the 2015-20 period, which describes how we will oversee the information that the largest 18 largest water and sewerage and water only companies (‘the water companies’) in England and Wales provide to customers. It explains the actions that we want companies to take. We initially published this document in June 2015. We updated it in July 2017. The updated document contains one policy change and some minor changes that do not represent a change to policy or intent. We have: • changed our policy on the length of time that companies should remain in the prescribed category from 18 months to 12 months, as already published in Company monitoring framework: 2016 assessment; • addressed an inconsistency in the format of the document, so that the assessment categories are explained in full, in one place; • clarified how we assess companies’ assurance to reflect our approach published in the 2016 assessment; and • made a number of minor changes to the wording to reflect that the company monitoring framework is an “up and running” tool and to improve the clarity or readability of the document.