Educational Testing has become an integral part school development in the UK. This kind of testing used to be an area exclusively dominated by Education Pyschologists, but the increasing importance of data (and the shortage of EPs in general) has meant more and more teachers are gaining qualifications that enable them to carry out tests, previously only available to EPs. Courses such as PATOSS and the CCET are recognized by the examination boards as qualifications that enable the bearer to write reports for access arrangements, and schools are realizing the value of this. This guide is intended to serve as an introduction for students embarking on such courses. It covers the basics of assessment and some of key themes surrounding Educational Testing.