All schools in England are required to have a SENCo. Although the DfE collects data relating to the demographics of this large population of teachers, this has not until now been analysed or published, meaning that much research relating to SENCos has had to proceed on the basis of estimates. A Freedom of Information request was made to the DfE, from which actual numbers could be established, with breakdowns by age, gender, ethnicity, position of responsibility and level of qualification. The data describe a professional who is most likely to be female, white and in the middle or towards to the end of their career, and often part-time. Most are on the class teacher pay scale rather than being on the leadership scale, with a minority holding a Master's level qualification. This article also evaluates several research studies in the field in the context of this analysis.