Dyscalculia has been described as a specific learning difficulty affecting the ability to acquire arithmetical skills. In recent years, it has become a topic for discussion in the popular media, yet there has been little research undertaken by educational psychologists. This paper provides a summary of neuroscientific research into the development of early number skills and considers the neurological and behavioural features of dyscalculia. Two fundamental questions are then discussed: Is one able to accurately assess for and identify dyscalculia?; Is it of benefit to children and young people to do so? The paper concludes by considering implications for practice.